wxGUI/widgets: add missing import

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@61549 15284696-431f-4ddb-bdfa-cd5b030d7da7

gui/wxpython/gui_core/widgets.py

@@ -44,6 +44,8 @@ import sys
 import string
 import re
 
+from datetime import datetime
+
 import wx
 import wx.lib.mixins.listctrl as listmix
 import wx.lib.scrolledpanel as SP