- Removed the `Process(string)` overload to make it extra clear that you must operate on project items. This way we also don't need to worry about the various formats of paths that can flow through the system.
- Updated tests to use the new project item format.
- Did a few formatting fixes on unrealted files.
#2049
- Make `RazorProjectEngine` call paths for all feature registrations.
- Add `DefaultMvcImportFeature` for latest and 1.X MVC.
- Ported `AddTargetExtension` and `AddDirective` to `RazorProjectEngineBuilderExtensions`.
- Added tests and a test file system project type.
- Moved obsolete `IRazorEngineBuilder` methods to the bottom of each file. Will actually obsolete the methods once `RazorProjectEngine` is working end-to-end.
#1828