Fixed GUI color map update (HACK)

Author: aashish24

Packages/vcs/Lib/VTKPlots.py

@@ -234,6 +234,7 @@ def createRenderer(self, *args, **kargs):
       return ren
 
   def update(self, *args, **kargs):
+      self._lastSize = -1
       if self.renWin:
           self.configureEvent(None,None)