Setup config environment variables

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
Use local for local data
ignore local virtualenv binary path
Merge pull request #2 from ddub/local-settings

Local settings