Reworked GUI and some importing.  Add detail about dependencies

There are quite a few changes, but I think they might pave the way toward what you are wanting.  The changes include:
- Adding lots of documentation to the gtk and pygtk libraries, installations, etc.
- Puts the mesonet request inside a method, which is defined inside the window's class
- Modifies the Window to actually retrieve the mesonet data and put it on the form itself
- Cleans up some spaces/tabs issues that were causing me to get an indentation error

I ran this on my Windows machine with Python 2.7 32-bit successfully.  I'll also try this on my Linux box.  Looking forward to hearing whether it works for you on Python 3.0 (64 bit?)!