Registry APIs: deprecate micro-syntax; introduce replacement API

Introduce a new, object-based API for all registry APIs; deprecate the
current string-based microsyntax registry APIs; and introduce a
`capabilities` property to the resolver to safely support existing
resolvers. Extend the new API for service and controller injections, and
deprecate their microsyntax for namespaced injections.

Today the registry APIs are all of shapes roughly like this:

    getOwner(this).lookup('service:session');

This RFC proposes that they would instead be written like this:

    getOwner(this).lookup({ type: 'service', name: 'session' })

Service and controller injections which include a namespace currently
look like this:

    class Example {
      @service('global@session')
      session;
    }

This RFC proposes that these would instead be written like this:

    class Example {
      @service({ namespace: 'global', name: 'session' })
      session;
    }