Don't push code coverage when on hhvm environment.

Signed-off-by: crynobone <crynobone@gmail.com>
Remove PHP 5.6 from allow failures.

Signed-off-by: crynobone <crynobone@gmail.com>
Update compiles list.

Signed-off-by: crynobone <crynobone@gmail.com>
Merge branch '2.1' into 2.2