Includes 5 new phpTests to check that the error message DOM_NOT_FOUND is properly...

Includes 5 new phpTests to check that the error message DOM_NOT_FOUND is properly raised by the method DOMNode::insertBefore(newNode, [refNode]).

Each file covers a different test case

    DOMNode_insertBefore_error2.phpt: refNode is a sibling of the node where newNode wanted to be inserted.
    DOMNode_insertBefore_error3.phpt: refNode is the parent of the node where newNode wanted to be inserted.
    DOMNode_insertBefore_error4.phpt: refNode is a brand new node.
    DOMNode_insertBefore_error5.phpt: refNode is a descendant (not child) of the node where newNode wanted to be inserted.
    DOMNode_insertBefore_error6.phpt: refNode is the node where newNode wanted to be inserted.