NetCore: MSDI refactor phase 2 (#9280)

* Moved adapters from Infra -> Core

* Allow Composition to accept a service collection instead of an IRegister

* Composition no longer takes IRegister as constructor arg

all tests passing

* Composition no longer implements IRegister

* Lose _uniques in Composition

* lose Composition OnCreatingFactory actions

* Clean up UmbracoCoreServiceCollectionExtensions & Composition

Less IFactory

* LightInject gone where TFW == netstandard2.0 || TFW == netcoreapp3.1

* Resolve dead code issues

* Rename IFactory methods to match IServiceProvider so they can be trivially swapped later.

* Rename IFactory methods to match IServiceProvider so they can be trivially swapped later (continued)

Thought the counts were low, it's mostly extension method usage

src/Umbraco.Core/Sections/SectionCollectionBuilder.cs

@@ -16,7 +16,7 @@ namespace Umbraco.Web.Sections
             // get the manifest parser just-in-time - injecting it in the ctor would mean that
             // simply getting the builder in order to configure the collection, would require
             // its dependencies too, and that can create cycles or other oddities
-            var manifestParser = factory.GetInstance<IManifestParser>();
+            var manifestParser = factory.GetRequiredService<IManifestParser>();
 
             return base.CreateItems(factory).Concat(manifestParser.Manifest.Sections);
         }