readme: add badges

crates.io used to show some automatically per badge configuration in the
crate toml files, however then they dropped this ([1]). crates now show
badges via embedding them in readme.md files.

shields.io is a popular service for constructing and serving badges, with
a lot of available customisation.

here i have selected the 'for-the-badge' style, which is similar to the
nice 'flat-square' style, but uses capital letters and a default later
height of 28px instead of 20px. I have used HTML for embedding them to
allow control over the size, which I have forced to 24px since 28px is just
too large. (there is a query-param available to control width but not
height for some reason).

notes:
 - for the min-rust-version badge, there were two different URL formats
   available for custom badges, I went with the 'static' form which makes
   use of a lot of query params.
 - for the min-rust-version badge, I had to use capitals for the service
   text to get it consistent with the rest, since it was not automatically
   capitalising it.
 - for the docs.rs one i had to use the crates.io one with a custom colour
   and service text specified, since shields.io has a mechanism in place
   for automatically building the latest crates.io version number into the
   crates.io badge, but does not have a similar specific badge-builder
   available for docs.rs badges. (and the badge you can get from docs.rs
   itself is a different style of course).
 - the message for the min-rust-version is '1.40%2B' which is '1.40+'!

i was inspired by the badges of the 'quote' crate.

[1]: rust-lang/crates.io#2436

README.md

@@ -1,6 +1,9 @@
 Overview
 ========
 
+[<img alt="travis.com" src="https://img.shields.io/travis/com/jnqnfe/pulse-binding-rust?style=for-the-badge" height="24">](https://travis-ci.com/jnqnfe/pulse-binding-rust)
+<img alt="license" src="https://img.shields.io/crates/l/libpulse-binding.svg?style=for-the-badge" height="24">
+
 This repository contains *sys* and *binding* libraries (crates) for connecting to PulseAudio (PA)
 from the Rust programming language.
 

pulse-binding-mainloop-glib/README.md

@@ -1,6 +1,12 @@
 libpulse_glib_binding
 =====================
 
+[<img alt="travis.com" src="https://img.shields.io/travis/com/jnqnfe/pulse-binding-rust?style=for-the-badge" height="24">](https://travis-ci.com/jnqnfe/pulse-binding-rust)
+[<img alt="crates.io" src="https://img.shields.io/crates/v/libpulse-glib-binding?style=for-the-badge" height="24">](https://crates.io/crates/libpulse-glib-binding)
+[<img alt="docs.rs" src="https://img.shields.io/crates/v/libpulse-glib-binding?color=5479ab&label=docs.rs&style=for-the-badge" height="24">](https://docs.rs/libpulse-glib-binding)
+<img alt="min-rust-version" src="https://img.shields.io/static/v1?label=RUST&message=1.40%2B&color=informational&style=for-the-badge" height="24">
+<img alt="license" src="https://img.shields.io/crates/l/libpulse-glib-binding.svg?style=for-the-badge" height="24">
+
 A Rust language binding for the PulseAudio libpulse-mainloop-glib library.
 
 ## Usage

pulse-binding-simple/README.md

@@ -1,6 +1,12 @@
 libpulse_simple_binding
 =======================
 
+[<img alt="travis.com" src="https://img.shields.io/travis/com/jnqnfe/pulse-binding-rust?style=for-the-badge" height="24">](https://travis-ci.com/jnqnfe/pulse-binding-rust)
+[<img alt="crates.io" src="https://img.shields.io/crates/v/libpulse-simple-binding?style=for-the-badge" height="24">](https://crates.io/crates/libpulse-simple-binding)
+[<img alt="docs.rs" src="https://img.shields.io/crates/v/libpulse-simple-binding?color=5479ab&label=docs.rs&style=for-the-badge" height="24">](https://docs.rs/libpulse-simple-binding)
+<img alt="min-rust-version" src="https://img.shields.io/static/v1?label=RUST&message=1.40%2B&color=informational&style=for-the-badge" height="24">
+<img alt="license" src="https://img.shields.io/crates/l/libpulse-simple-binding.svg?style=for-the-badge" height="24">
+
 A Rust language binding for the PulseAudio libpulse-simple library.
 
 ## Usage

pulse-binding/README.md

@@ -1,6 +1,12 @@
 libpulse_binding
 ================
 
+[<img alt="travis.com" src="https://img.shields.io/travis/com/jnqnfe/pulse-binding-rust?style=for-the-badge" height="24">](https://travis-ci.com/jnqnfe/pulse-binding-rust)
+[<img alt="crates.io" src="https://img.shields.io/crates/v/libpulse-binding?style=for-the-badge" height="24">](https://crates.io/crates/libpulse-binding)
+[<img alt="docs.rs" src="https://img.shields.io/crates/v/libpulse-binding?color=5479ab&label=docs.rs&style=for-the-badge" height="24">](https://docs.rs/libpulse-binding)
+<img alt="min-rust-version" src="https://img.shields.io/static/v1?label=RUST&message=1.40%2B&color=informational&style=for-the-badge" height="24">
+<img alt="license" src="https://img.shields.io/crates/l/libpulse-binding.svg?style=for-the-badge" height="24">
+
 A Rust language binding for the PulseAudio libpulse library.
 
 ## Usage

pulse-sys-mainloop-glib/README.md

@@ -1,6 +1,12 @@
 libpulse_mainloop_glib_sys
 ==========================
 
+[<img alt="travis.com" src="https://img.shields.io/travis/com/jnqnfe/pulse-binding-rust?style=for-the-badge" height="24">](https://travis-ci.com/jnqnfe/pulse-binding-rust)
+[<img alt="crates.io" src="https://img.shields.io/crates/v/libpulse-mainloop-glib-sys?style=for-the-badge" height="24">](https://crates.io/crates/libpulse-mainloop-glib-sys)
+[<img alt="docs.rs" src="https://img.shields.io/crates/v/libpulse-mainloop-glib-sys?color=5479ab&label=docs.rs&style=for-the-badge" height="24">](https://docs.rs/libpulse-mainloop-glib-sys)
+<img alt="min-rust-version" src="https://img.shields.io/static/v1?label=RUST&message=1.40%2B&color=informational&style=for-the-badge" height="24">
+<img alt="license" src="https://img.shields.io/crates/l/libpulse-mainloop-glib-sys.svg?style=for-the-badge" height="24">
+
 A Rust language linking library for the PulseAudio libpulse-mainloop-glib library. See also the
 higher-level `libpulse_glib_binding` crate.
 

pulse-sys-simple/README.md

@@ -1,6 +1,12 @@
 libpulse_simple_sys
 ===================
 
+[<img alt="travis.com" src="https://img.shields.io/travis/com/jnqnfe/pulse-binding-rust?style=for-the-badge" height="24">](https://travis-ci.com/jnqnfe/pulse-binding-rust)
+[<img alt="crates.io" src="https://img.shields.io/crates/v/libpulse-simple-sys?style=for-the-badge" height="24">](https://crates.io/crates/libpulse-simple-sys)
+[<img alt="docs.rs" src="https://img.shields.io/crates/v/libpulse-simple-sys?color=5479ab&label=docs.rs&style=for-the-badge" height="24">](https://docs.rs/libpulse-simple-sys)
+<img alt="min-rust-version" src="https://img.shields.io/static/v1?label=RUST&message=1.40%2B&color=informational&style=for-the-badge" height="24">
+<img alt="license" src="https://img.shields.io/crates/l/libpulse-simple-sys.svg?style=for-the-badge" height="24">
+
 A Rust language linking library for the PulseAudio libpulse-simple library. See also the
 higher-level `libpulse_simple_binding` crate.
 

pulse-sys/README.md

@@ -1,6 +1,12 @@
 libpulse_sys
 ============
 
+[<img alt="travis.com" src="https://img.shields.io/travis/com/jnqnfe/pulse-binding-rust?style=for-the-badge" height="24">](https://travis-ci.com/jnqnfe/pulse-binding-rust)
+[<img alt="crates.io" src="https://img.shields.io/crates/v/libpulse-sys?style=for-the-badge" height="24">](https://crates.io/crates/libpulse-sys)
+[<img alt="docs.rs" src="https://img.shields.io/crates/v/libpulse-sys?color=5479ab&label=docs.rs&style=for-the-badge" height="24">](https://docs.rs/libpulse-sys)
+<img alt="min-rust-version" src="https://img.shields.io/static/v1?label=RUST&message=1.40%2B&color=informational&style=for-the-badge" height="24">
+<img alt="license" src="https://img.shields.io/crates/l/libpulse-sys.svg?style=for-the-badge" height="24">
+
 A Rust language linking library for the PulseAudio libpulse library. See also the higher-level
 `libpulse_binding` crate.