Fix forgotten import of Arrow class in the GUI => probably an exception in pypi package...

gui/cadbiom_gui/gt_gui/chart_controler.py

@@ -48,7 +48,7 @@ Main gui controler with auxiliary classes
 from math import sqrt
 from gtk.gdk import Cursor, ARROW, BOTTOM_LEFT_CORNER, BOTTOM_RIGHT_CORNER,\
                     TOP_LEFT_CORNER, TOP_RIGHT_CORNER, LINE_ON_OFF_DASH
-from graphics.drawing_style import  Arrow
+from cadbiom_gui.gt_gui.graphics.drawing_style import Arrow
 
 
 import gtk