Changes:
* Update docs
* Update browser test artifacts
* Update comments
* Update phpunit test groups
* Update phpunit test namespace
* Update `die` when MobileFrontend not installed
* Remove the migrate script which is no longer needed
Change-Id: I83432b3f7f0bcd07ed08259972b8ff89147104b6
This moves all browser tests from MobileFrontend to the Minerva repo
in preparation for separating the two.
Note, this means browser tests will exist in both repositories for a
period of time. This is important and necessary to ensure we do not
break anything.
See:
https://lists.wikimedia.org/pipermail/mobile-l/2017-July/010536.html
Bug: T168758
Change-Id: I84ae3ea14191f672cabcd52020e80b0a40a72ce1