Fix run-tests.php with Valgrind >= 3.10.0.

The version test that we had in run-tests.php assumed that the major and minor
version numbers were always single digits. This removes that assumption and
also uses version_compare() for the comparison instead of naively converting it
to an integer.
Merge branch 'PHP-5.4' into PHP-5.5

* PHP-5.4:
  Fix run-tests.php with Valgrind >= 3.10.0.

Conflicts:
	run-tests.php