Changed test script in .travis.yml to nosetests
Added ``mocker`` to requirements.txt
Fixed a typo in .travis.yml

``install`` command had ``--user-mirrors`` in it
instead of ``--use-mirrors``.
Vagrantfile shortened to essentials, ``provision.sh`` added.
``.gitignore`` changed, no .DS* for Macs.
Added ``.vagrant`` to ``.gitignore``
Merge branch 'master' into specs

Conflicts:
	.gitignore
	.travis.yml
	requirements.txt
Resolved merge conflicts.