Edited Issue: MustFix: Nesting an .edmx under a project folder causes .tt to stop generating after save [453]

Repro steps:
1. Create a project
2. Add a project folder ("Models")
3. Add a new .edmx ("Model1") into the project folder
4. Add an entity ("car") and save.

Expected:
A new Car.cs file under Model1.tt, as well as related updates to Model1.Context.cs

Actual:
No updates to generated code

Workarounds:
- Right click on .tt file and select "Run Custom Tool"
- Drag .edmx out of the project folder