Merge pull request #41 from Wohlstand/master

Repo Sync
Added double-clicking into item selection dialog
Organizing of level items
Fixed layer switching

Layer will be reseted to "default" if selected item of another ID or of another type,
but never if you switching the "rectangle", "line" or "flood fill" modes
Merge pull request #164 from Wohlhabend-Networks/master

Repo Sync