* Handle links to empty-string href, resolved against base href
Needed to change the URLs used in E2E tests to be able to cover this (i.e., removed the /RouterTest prefixes so the default relative URL became an empty string)
* Change links in StandaloneApp sample to be relative
* Standardize on base URIs having trailing slash everywhere
Hence also change terminology from "base URI prefix" to simply "base URI"
* Handle link highlighting when visiting base-href-but-without-trailing-slash
* Removing leading slashes from base-relative URLs in templates
Steve Sanderson