Merge branch 'PHP-5.5'

* PHP-5.5:
  Fixed inconsequential bug in strtr()
  UPGRADING.INTERNALS: document zend_qsort_r
  Add zend_qsort_r & use it in strtr
  NEWS for bug #63893
  Remove _GNU_SOURCE, add local heap sort
  The compiler can figure this out
  Remove unused block
  strtr() with 2nd param array - optimization
  Refactoring, bugs & leaks
  Optimize strtr w/ 2nd arg array