A bit of refactoring in the unit tests for haas.model.

In particular:

* Database setup is now handled as part of a superclass. This will make
  it easier to add additional test cases.
* More docstrings.
Basic test that actual insertion into the db works.

Right now this just covers the User class, but there is a base class
that will make similar test cases easy to write.
Added more database insertion tests

Specifically, added tests for:

* Nic
* Switch
Reworked rest api mapping docs.

Made it generally more consistent.
Fixed a formatting issue.

Adding the bit of text between the list and the full spec convinces github to make the summary a code block, which is what was intended.
The {h,}nic in {connect,detach}_network is now part of the url.

Previously it was passed in as part of the body.
Deleted some trailing whitespace.
test/unit/api.py: Fixed a few issues caught by pyflakes

* Removed haas.config import - it was unused.
* Two pep8 violations; space after the comma and two blank lines between
  top-level constructs.
Wrote some tests exposing breakage in group_{add,remove}_user.
Fixed some bogus conditions.

These were causing the breakage caught by the tests in the previous
commit. I'm not sure why someone thought this would test for set
membership.
Whitespace.
Merge branch 'rest-api-docs' into project_deploy

Conflicts:
	docs/rest_api.md
Merge branch 'devel' into model-tests

Conflicts:
	haas/_tests/model.py
Added a coverage tool to requirements.txt, and some docs.

I also added `.coverage` to .gitignore; the tool seems to generate this.
Improved test coverage of haas.model.

Added tests which exercise the methods of everything the module except:

* the `Vlan` class, which needs to be ripped out in favor of `Network`,
* the `Port` class -- my intuition is that giving it its own label is
  excessive, and I want to revisit the interface to this.

In addtion, there is a config-related if-statement that is not covered,
in `init_db`.
Merge branch 'haas.api-fixes' into coverage
tests: better names/fixed docs for some of the api tests.
Test suite additions

Some of the existing group-related tests are now stricter, and a few new
ones have been added.

Some of these are actually failing now.
Fixed some failing tests.

There was a mis-named attribute (or arguably just inconsistently named,
but this makes more sense).
More tests.