Added DeleteProject action.
Adapted GalleryGrid to support deletions.
Implemented delete functionality for galleries.
Fixed severall deletion bugs, improved galleries deleting functionality.
Small bug fix: changed Scene to EditorScene.
Added DeleteProjectTest
Merge pull request #165 from RotaruDan/DeleteFromGalleries

Delete projects/scenes from galleries.
Fixes #173
Fix #94 I have the feeling I had to fix the same thing in many different places: we should control the canonical path in only one place
Updating empty game for testing
Minor typo
Adding new fixme
Merge pull request #177 from angeldelblanco/issue-94

Issue 94