I18N help messages.
Adds HelpMessage.
Adds HelpSequence and creates helps messages for some views.
MockupViews displays a HelpSequence when setting a view.
Adds PositionedHiddenPanel.
Refactoring for IconWithPanel. SwarchWidget, HiddenPanel and PrefabPanel fixes.
Merge pull request #730 from RotaruDan/cameraView

Adds HelpMessage management to eAdventure Mockup.
Small Selection and Views improvements.
Templates now creates elements centered in the screen.
Improves ImportElement action.
Reduces Assets#LOAD_TIME_SLOT_DURATION reducing the UI thread stuttering while loading big amounts of textures.
Improves TakePicture action and also Platform#askFotFile(...) method in Android.
PlayView loads the current game correctly.
Adds BrushStrokes.
Adds PaintToolbar.
Adds functionality to some buttons from the TopEditionToolbar.
Adds MockupSceneEditor.