More fixes for nodelist array access
- testing for null property read
- no zval copying if the type is already long
- memory fix for master
Merge branch 'PHP-5.6'

* PHP-5.6:
  More fixes for nodelist array access
  - testing for null property read
  - no zval copying if the type is already long
  - memory fix for master
  - use zend_long for offset

Conflicts:
	ext/dom/php_dom.c