First pass at this. Untested code. Want it committed before I go to sleep and lose my place.
Adding a transaction() method which returns the connection. This allows using the connection as a context manager for transactions.
Adding more untested code, preparing to implement tests.
Added ngcccbase package. Moved txdb.py into it. This breaks wallet_model.py until I pull from jimmysong.
Merge remote-tracking branch 'jimmysong/master' into txdb
Changing import.
Initial commit of tests.
Pass the first two tests.
Added storage test.
Test retrieval as well.
Fixed tests.
Removed some commented out dead code.
Merged back from bitcoinx main branch.
Merge branch 'txdb' of https://github.com/Ademan/ngcccbase

Conflicts:
	meat.py
	wallet_controller.py
	wallet_model.py