Creation of the Invoker class
Undo / Redo working for the moving command on a Entity
Creation of element panel and try to connect with the graphics elements
Opacity connections first try : need a new design
Saving tileset okay, and first try saving level
Tinyxml library suppression
Merge branch 'patternCommand'

Conflicts:
	IndieLibEditor.pro.user
	src/graphics/scene.cpp