[Matplotlib-users] Fixed wxcursor_demo.py example, please commit

I am making a new wxcursor_demo.py example I attach it to this mail.

If anybody can help me iron those wrinkles I think we can make a great 
wxcursor_demo example.

I am not proud of invoking the SetCursor method on the wx.EVT_PAINT 
event but it works ...

The present wxcursor_demo example is broken because:
    - Does not follow wx coding standards, not pythonic at all.
    - Very complicated example to follow and long.
    - Some nonsensical code such as the Time and Price part.
    - The wx "hand draw", crosshair has lots of disadvantages (you get 
the mouse pointer right next to it so it's useless for picking pixels in 
images.)
    - The users should have access to wx.StockCursor, with the current 
example every cursor has to be " hand drawn"

          This said, I thank a lot the person who started the example 
since I used it as a starting point.

                   Any feedback would be appreciated.


   
                                                                         
                     Daniel.