Image tool's image object set to nothing on hit test

[Steven Sproat]

Whyteboard 0.41.1
Operating System: Windows NT 6.1 (build 7600)
Screen Resolution: 1366x768
Python Version: 2.6.4 (r264:75708, Oct 26 2009, 08:23:19) [MSC v.1500 32 bit (Intel)]
wxPython Version: 2.8.10.1 (msw-unicode)
wxPython Info: (__WXMSW__, wxMSW, unicode, wx-assertions-on, SWIG-1.3.29)
Python Encoding: Default=ascii File=mbcs
wxPython Encoding: utf-8
System Architecture: 32bit x86
Byte order: little
Frozen: windows_exe

 File \"whyteboard\\gui\\canvas.pyo\", line 168, in motion
 File \"whyteboard\\gui\\canvas.pyo\", line 217, in select_tool_cursor
 File \"whyteboard\\gui\\canvas.pyo\", line 244, in select_tool_cursor_change
 File \"whyteboard\\tools.pyo\", line 1613, in hit_test
AttributeError: \'NoneType\' object has no attribute \'GetSize\'

Image in tools.py:

    def hit_test(self, x, y):
        width, height = self.image.GetSize()

[Steven Sproat (sproaty)]

have put a guard around the code in case we have an invalid image....should fix; but the bug report indicates a different issue - image should never be Nothing.