[Bug-gnubg] Relational database

[Jon Kinsey]

I've just checked in some more code for the relational database.  I've 
fleshed out some of the functionality and started the gtk interface.

I had to make a few database dependent changes to database.py and have 
added a database type variable, it would be good if someone could test 
the code with a different database.

If you want to try it with windows you will need python, sqlite and 
pysqlite installed (and obviously build the latest code with python 
support).

I've not added the multiple environment support yet, and I'm also 
planning on adding the code to detect if a match is already present in 
the database.

Jon