New tests

EXTREMELY IMPORTANT!!!! When merged, the next thing to merge is the new_tests branch in mist.core, otherwise we'll have import problems with mist.core.

What is this:
First batch of new_tests, mainly GUI tests using behave, behaving, selenium.

Includes "everyday" tests to be run after each Pull request. Also includes multi-provisioning tests, to be run every week or so, that test the provisiong of machines in many providers.

There is a src/mist/io/tests/settings.py.dist that needs to be copied to src/mist/io/tests/settings.py if you want to run the tests.

Documentation of the whole testing procedure will come soon when the whole test migration is complete