Very beginnings of a REST api server.

Really, this is just a skeleton of a flask app, plus some database
intialization.
Merge branch 'newapi' into api_server
Debug mode, for now.
Create/delete users, and change passwords via the rest api.

There are still some design issues to work out; see the comments.
Also, we're not doing authentication/authorization at all yet.
Started a separate module for the public api independent of HTTP.

See the docstring.
api_server now uses the haas.api module.

For some reason, enabling debug mode causes the module to be unable
to import things correctly from the source directory; you have to
actually install the package via setup.py. Need to figure out why.
Removed a comment.

I'm pretty sure flask already does what the comment is suggesting.
Added a docstring for api_function.
Merge branch 'newapi' into api_server
Merge pull request #69 from CCI-MOC/api_server

Api server (WIP)