Added a specific label to grouping level widget

Modified the label of an IWdidget derived class for a better display

MDANSE/Framework/Widgets/GroupingLevelWidget.py

@@ -35,4 +35,6 @@ from MDANSE.Framework.Widgets.SingleChoiceWidget import SingleChoiceWidget
 class GroupingLevelWidget(SingleChoiceWidget):
 
     type = "grouping_level"
+    
+    label = "Group coordinates by"
 

MDANSE/Framework/Widgets/IWidget.py

@@ -53,7 +53,7 @@ class IWidget(wx.Panel):
                                 
         self._configurator = configurator
                                                         
-        self._label = name
+        self._label = ' '.join(name.capitalize().split('_'))
                         
         self.initialize()