MVC functional test cleanup part 1
- #3612 (subpart 1 of 2)
- delete six sites and associated tests entirely
- `ActionResultsWebSite`
- `ActivatorWebSite`
- `ControllerDiscoveryConventionsWebSite`
- `LoggingWebSite`
- `LowercaseUrlsWebSite`
- `ModelBindingWebSite`, now covered in integration tests
- remove now-unused `FilteredDefaultAssemblyProviderFixture`, `LoggingAssert` and `LoggingExtensions`
- move six test web sites into `./samples`
- `CustomRouteWebSite` -> `CustomRouteSample.Web`
- `FormatFilterWebSite` -> `FormatFilterSample.Web`
- `InlineConstraintsWebSite` -> `InlineConstraintSample.Web` (now singular)
- `JsonPatchWebSite` -> `JsonPatchSample.Web`
- `LocalizationWebSite` -> `LocalizationSample.Web`
- `RazorEmbeddedViewsWebSite` -> `EmbeddedViewSample.Web` (no longer "Razor" and now singular)
- do some cleanup: remove test dependencies, shorten sample controller names, use more attribute routing
- correct "license" spelling in `ApplicationModelWebSite`
