Merge pull request #87 from jparty/urbapp_last

Add the choice of intersecting a zone with older ones or not...
Fixing the bug of the addDialogFragment.
Merge branch 'dev' of https://github.com/Mendroyxx/FeatureApp.git into urbapp_last
Reduce the size of the buttons is CharacteristicsFragment.
Move the attribute selected and linkedPixelGeom from PixelGeom to Element to make it more logical and avoid issues when editing the PixelGeom of a (weak-)linked Element.