Switch to Flask basis.  Only some of requirements met so far.
See https://github.com/18F/afsmallbiz/issues/76

Simplistic architecture so far for Flask.
existing tests now pass
see https://github.com/18F/afsmallbiz/issues/76
Moved models to their own subpackage
see https://github.com/18F/afsmallbiz/issues/76
Minor PEP8 cleanups
see https://github.com/18F/afsmallbiz/issues/76
Whitespace fixes
see https://github.com/18F/afsmallbiz/issues/76
remove unused imports
see https://github.com/18F/afsmallbiz/issues/76
added comments
see https://github.com/18F/afsmallbiz/issues/76
Working on import errors when running script directly
Ugly, ugly brute-force append to sys.path to make imports work.  Ugh.
See https://github.com/18F/afsmallbiz/issues/76
Added messages to status codes for error responses
See https://github.com/18F/afsmallbiz/issues/76

Also created entry point, so can be run with ``codetalker_server``
Change field name from _year to year
Merge pull request #20 from 18F/flask

Switch to Flask basis.