DispatchingContentDirectory, broadcasts search capabilities, and removes
an assignment that was not longer necessary.
Also added a couple of comments for clarity on the '- All Albums-' options.
This replaces the existing FolderBasedContentDirectory with a new
DispatchingContentDirectory. The new system then dispatches requests to
subclasses of UpnpContentProcessor, which then handle the requests as
appropriate.
This version also implements a new searchByName method in SearchService,
which is used to provide artist, album, and track search functionality
for the upnp service.
Allen Petersen