Add "kRewriteUrlProcessor::moreToParse" method for checking if not all URL fragments were parsed

Since rewrite listeners were first introduced in #0000098 I we've used them on several projects. And I wanted to share some improvements we've done with the community.

That includes following changes to widget rewrite listener (in Development Kit module):
1. reduced SQL count when building url because of actual url part passed to rewrite builder right from $object (see WidgetTagProcessor::ItemLink tag)
2. always use physical template when building url when deciding whatever to include it in url or not (when it's default item detail template)
3. allow for rewrite parser to intellectually search for url part it require ignoring changes made to other parts of url:

• worked before: "/widgets/widget-filename.html"
• works now: "/text-before/widgets/widget-filename/text-after"
  4. easily check if there are unparsed url parts and there are none then set rewrite parser default item detail template