feat(PHP): Remove deprecated preg_replace with '/e' modifier (refs #5034)

As we are now using PHP >= 5.4, we can dump the remaining preg_replace()
with '/e' modifier and use preg_replace_callback() with anonymous
functions.

Also:
- Changed preg_replace_callback() using array() callbacks with anonymous
  function callbacks
Merge pull request #1365 from eguaj/3.2-A5034

feat(PHP): Remove deprecated preg_replace with '/e' modifier (closes #5034)