[Tests] Tests on php 5.5 should pass

Because php 5.5 is stable now
merged branch lyrixx/php55 (PR #8559)

This PR was merged into the 2.2 branch.

Discussion
----------

[Tests] Tests on php 5.5 should pass

Because php 5.5 is stable now

Commits
-------

0086ee3 [Tests] Tests on php 5.5 should pass