Removed Caps.Web.Mvc and Demo Website.

Websites now use the Web API Services of the CMS to load data.
Fixed a bug where CapsSiteMapNode returned...

a malformed url.
- Made sure, the root node gets a localized url. Otherwise we fall back
to default language when navigating to the root node.
- Renamed DemoWebsite2 to DemoWebsite
- Show root node content on start page of demo website.
- Show breadcrumbs in demo website.
- Misc visual changes in demo website.
Create cropped thumbnails by default. Use Thumb...

...nail-Route also if only the size-Parameter is specified.
- Fixed a Problem in CapsDbContextProvider. The IPrincipal-Instance in
the constructor was not authenticated and never got authenticated. Use
Thread.CurrentPrincipal instead.
- Prevent Null-Reference-Exception in DefaultSiteMapBuilder when a
Teaser has no redirect.