Pagecontainer: Remove code dealing with subPageUrlKey special case
Path: Remove code dealing with subPageUrlKey
Path: No longer test for correct stripping of subPageUrlKey
Navigation: Make sure location is encoded when going to a funky page
Init: Correctly assign data-url for initial page
Init: Make sure "data-url" attribute for initial page is decoded
Pagecontainer: Escape dataUrl when trying to find page based on it

Fixes gh-1383
Pagecontainer: Decode URI when assigning to "data-url" during _parse()
Pagecontainer: Use decoded URL to build selector for data-url
Pagecontainer: Call convertUrlToDataUrl() via _createDataUrl()
Path: Always uri-decode when computing dataUrl
Pagecontainer: Remove extra decoding step, now part of _createDataUrl()

This also removes the possibility that a URL gets double-decoded.
Pagecontainer: Test behavior of _find() in the face of weird URLs
Navigation: Use data-url retrieved from Ajax request in its encoded form