Multiple-segments simple address starts with single-segment simple address should be routable

Description

Assuming there are pages with simple addresses, such as

• localhost/en/first/
• localhost/en/first/second/
• localhost/en/first/second/third/

You can route simple addresses now. Previously, requests to the last two returned HTTP 404.

You can also route multiple-segments simple addresses with custom controller action,  such as localhost/en/several/segments/customcontrolleraction

However, even though simple addresses with multiple segments are supported, you should not use them because they aren't simple anymore.

Note: UrlResolver has a small non-breaking change compared to the previous release, where it can resolve both absolute and relative simple address with the simple address segment being either encoded or unencoded (IRI support.) In this release, UrlResolver does not resolve relative encoded simple address.  UrlResolver should always be able to resolve links it has generated itself, but since it does not generate encoded links, it isn't a required to resolve encoded links.