Closing repo

As per our discussion at last week's meeting [1].

Note that the `old-master` [2] branch has been created for archive purposes.

[1] https://wiki.mozilla.org/QA/Execution/Web_Testing/Meetings/2014-06-12#Action_Items_.2F_Takeaways_from_Last_Week
[2] https://github.com/mozilla/input-tests/tree/old-master