getHref2Html: Avoid Recursion on Odd-Parent Traversal

[drfho]

Ref: #508

When ZMSObjectSet lists ZMSTextarea the link creation may end in a recursion (due to self.getPhysicalPath()[2:]), because parent does not provide the needed attributes.
To make getHref2Html() resilient aganist the acquisition edge cases, there is a new parameter "resilient" that can be used explictly or is implicitly used as a fallback: resilient=False is the default and this down-compatible:

ZMS/Products/zms/zmsobject.py

Lines 1090 to 1098 in 4815bbe

	if not self.isPage():
	if not resilient:
	try:
	parent = self.getParentNode()
	pageext = parent.getPageExt(REQUEST)
	href = parent.getHref2Html(fct, pageext, REQUEST, resilient=False)
	if href.find('#') > 0:
	href = href[:href.find('#')]
	href += '#' + self.id