Added extensions on IServiceCollection

[mburumaxwell]

This adds new extensions on IServiceCollection similar to those on IHostBuilder. Also changed the implementation of the ones in IHostBuilder to rely on the new extensions for easier maintenance in the future. The implementation logic as pertains to registration of services remains the same.

Fixes: #66, #68

[nblumhardt]

LGTM! Thanks @mburumaxwell and @sungam3r for the review 👍

I'll bump the dev package version to 5.1.0-* to indicate new feature additions.

[AraHaan]

Can a followup pr be made to split the servicecollection versions over into an Serilog.Extensions.DependencyInjection library so that way those who do not want to use the hosting packages could get the benefits of using the new extensions?

Also, then the hosting package could depend on that package as well which should be ok as Microsoft.Extensions.DependencyInjection would be provided anyways.

[mburumaxwell]

LGTM! Thanks @mburumaxwell and @sungam3r for the review 👍

I'll bump the dev package version to 5.1.0-* to indicate new feature additions.

Cool. Looking forward to the release.

[mburumaxwell]

Can a followup pr be made to split the servicecollection versions over into an Serilog.Extensions.DependencyInjection library so that way those who do not want to use the hosting packages could get the benefits of using the new extensions?

Also, then the hosting package could depend on that package as well which should be ok as Microsoft.Extensions.DependencyInjection would be provided anyways.

This makes sense. Maybe you can do the PR?

If we have to move things, instead of a new package, I'd move the extensions to Serilog.Extensions.Logging (lives in a different repository) which is referenced by the hosting one here. In such a case, I wonder if the hosting package would still be needed seeing that one can do it. Maybe that's a different discussion?

[AraHaan]

Yeah, I think putting it in the logging package would be better as well. And yes, I think the hosting package can be deprecated after this (which would help you guys more with less packages to maintain).

[mburumaxwell]

@AraHaan I believe that's for @nblumhardt to decide, being the maintainer.

[AraHaan]

Yeah, I know that. I was just saying what I was thinking as well.