Moves the Z-index buttons and the remove button from the ConfigurationShutter to the MenuBar,
Moves the GraphicalElement buttons from the ElementShutter to the MenuBar,
Removes the ElementShutter and the Shutter class,
Removes unused functions in the ConfigurationShutter,
Correction of the overlapping (back/front) of the GraphicalElement (it was broken).
Fix merge
Change the ConfigurationAttribute class and CAList class to interfaces,
Those two new interfaces are implemented into the SimpleCA class and SimpleListCA class,
Function lock and unlock are changed into setLockt(boolean),
The equals function returns if the two properties have the same values,
The isSameProperties returns if the two CA have the same name.
Changes the GraphicalElement class, CartographiqueElement class, IllustrationElement class to interfaces,
All of those classes are implemented into simple classes.
Now the Document GE is a normal GraphicalElement,
The interfaces AlwaysOnFront and AlwaysOnBack force a GraphicalElement to be placed at the front or back of the CompositionArea.
Correction of the exeption getted because of the z-index.
Now the plugin is launched in OrbisGIS, in the tools menu.
Corrects the exception getted when a GE is dragged over the document border.
Correction of the exception getted on removing a GE.
Merge pull request #2 from SPalominos/pushToirst

PR : Change Document behaviour, in GraphicalElement and ConfigurationAttribute abstract classes changed for interfaces.
Few corrections on the z-index changes,
Delete the ElementShutter and the Shutter class,
Change the CA and GE abstract classes into interfaces,
The Document GE have now the same behavior that the other GE.