[DF-867] Added * on tabs for scenes with unsaved changes.
[DF-867] Added placeOnLandscape/SnapToLandscape functionality.
Merge branch 'development' of https://github.com/dava/dava.framework into development

Conflicts:
	Tools/ResourceEditor/DataQt/mainwindow.ui
[DF-1346] Added new commands into sceneTree context menu
[DF-1393] selectionSystem now can lock it current selection
[DF-1346] Now saving current selection, when switching between tabs
[DF-867] Fixed "save" for new scenes to be "save as"
Merge branch 'development' of https://github.com/dava/dava.framework into development
[DF-1346] Added filtering into scene tree
[DF-867] Property editor now handle when active scene change
Merge branch 'development' of https://github.com/dava/dava.framework into development