Convenience method added to ResourceManage to get all packages.
Refactoring: Using that method first in ProjectSettingsWindowsController.
Refactoring:
Inject ResourceManager instead of accessing singleton.
Code formatted.
Removed obsolete #imports.
ProjectSettings property made strong.
Bugfix for #922 - All package could be deleted.
Merge pull request #1008 from NickyWeber/bugfix/#922_all_packages_can_be_deleted

Bugfix/#922 all packages can be deleted