Local settings

Allows an external config file to be set which can contain installation
specific settings to be stored

$ cat config.py | sed "/^SECRET_KEY = / s/=.*/= $RANDOM/" > ~/intbass-settings.py
$ INTBASS_SETTINGS=~/intbass-settings.py python run.py

The default config will load in "development mode" that is which minimal
external dependencies and on the local machine