attempts to speed gfx up
added path to gfx (line, rectangle and arrow are now special case for path)
added enable attribute to gfx (events are now disabled by default)
still work to do for path (fill)color
reworked color management in GuiGfx
added opacity option to colors in GFXs
Rajoue du texte sur les Gfx
Merge branch 'master' of ssh://pumpkin.laas.fr/gate

Conflicts:
	ws-client-gwt/src/fr/laas/gate/GuiGFX.java