[modules/battery] Use theme.exclude to not show suffix

If battery module should be "undecorated", do not show the suffix.

fixes #401

bumblebee/modules/battery.py

@@ -48,6 +48,8 @@ class Module(bumblebee.engine.Module):
             self.capacity(widget)
         while len(widgets) > 0: del widgets[0]
         for widget in new_widgets:
+            if bumblebee.util.asbool(self.parameter("decorate", True)) == False:
+                widget.set("theme.exclude", "suffix")
             widgets.append(widget)
         self._widgets = widgets
 
@@ -103,9 +105,6 @@ class Module(bumblebee.engine.Module):
         elif capacity < int(self.parameter("warning", 20)):
             state.append("warning")
 
-        if bumblebee.util.asbool(self.parameter("decorate", True)) == False:
-            return state
-
         if widget.get("ac"):
             state.append("AC")
         else: