Merge pull request #21 from dornhege/groovy-devel

I confirmed that the proposed part (to avoid float value rounded) works, by unit test file I'll upload later.

I haven't been able to test With real robots -- I only have an access to `PR2`, of which dashboard overrides `BatteryDashWidget`.`update_time` method.

rqt_robot_dashboard/src/rqt_robot_dashboard/battery_dash_widget.py

@@ -77,4 +77,8 @@ def _update_state(self, state):
             self.setIcon(self._icons[state])
 
     def update_time(self, value):
-        self.setToolTip("%s%% remaining" % value)
+        try:
+            fval = float(value)
+            self.setToolTip("%s: %.2f%% remaining" % (self.name, fval))
+        except ValueError:
+            self.setToolTip("%s: %s%% remaining" % (self.name, value))