Give a bit more information from APIError to the client.

We're putting a json object in the body of the response when reporting
an error to the client. This is at least a step closer to what we want.

We now also have the ability to override the http status code.
Generalize and fix create_dell_vlans

It now should work, again, and should even work for drivers other than the
dell driver.
Merge pull request #253 from gsilvis/fix-create-dell-vlans

Generalize and fix create_dell_vlans
Merge branch 'regeneralize-deployment' into clear-setup-deployment-tests
Clear network config before deployment tests
Document regex in Dell switch driver
Merge pull request #255 from gsilvis/regeneralize-deployment

Regeneralize deployment
Merge pull request #256 from gsilvis/clear-setup-deployment-tests

Clear switch configuration before each deployment test
added query call for networks associated to a project, and tests to check a
standard return and null return
Merge pull request #258 from lokI8/network_query

added query call for networks associated to a project
Allow multiple headnodes per project
Improve error messages reported to the client.

This resolves #252.
Remove unneeded dependencies.

We're no longer using tabulate or Flask-HTTPAuth.
Specify package versions in requirements.txt

This resolves #100.
Add a large amount of documentation to haas.model.
Report coverage info by default when running tests.
Update testing docs to reflect the current state.

`docs/testing.md` was starting to succumb to bitrot.
Merge pull request #263 from zenhack/requirements-versions

Requirements versions
Merge pull request #262 from zenhack/better-error-messages

Improve error messages reported to the client.
Merge pull request #260 from zenhack/model-docs

Add a large amount of documentation to haas.model.