Fix test_settings_change_keyboard_language.py
test_ch_keyboard_language - erroneously xfailed, unxfailing
Merge pull request #1062 from zacc/unxfail_keyb_test

Unxfail test_change_keyboard_language
Merge pull request #1015 from davehunt/html-report2

HTML report
Update Travis CI configuration to run only on master branch against the latest mozilla-central nightly build
Skip email tests if account details are not present in test variables
Use SkipTest from Marionette instead of unittest
Switching to Twitter, as Lanyrd app is not appearing in results on B2G desktop
Wait for the browser tab list to be shown/hidden fully