Added Touchability component and actions
Added TouchabilityPrefabPanel and refactored VisibilityPanel
Improvements in NavigationButton and DeparturePanel.
added forgotten doc.
Merge pull request #735 from gorco/BlockPanel

Block panel
Reduces threshold and distance tolerance in MockupImageProcessor.
Disables the collider drawing while playing in Mockup.
Improves SceneItem and ProjectItem. ScenesView and ProjectsView fixes.
Fixes BrushStrokes and MeshHelper.
Improves PaintToolbar functionality.
Improves MockupSceneEditor: disables multiple selection and nested group edition, pinch and zoom functionality, clipping, etc.
Adds ElementContext to the Edition view and associated functionality: clone, erase, toFront, toBack, etc.
Adds OthersWidget.
Some UI widgets improvements.
eAdventure Mockup skin improvements.
Views improvements.
Minor changes/fixes.
Some fixes after rebasing.