#163 fulltext album search

[Brett Kerwin]

Below is a patch which implements fulltext search as described here.

Implementation is a bit of a hack and should be improved by someone more knowledgeable about dlna than me. But it works, at least with BubbleUPNP and with the Denon client.

When searching for a string, the matching albums are not only those whose title contains the string: an album matches as soon as each word of the string is contained in the title or artist name of some track or of the album (different words may appear in different places; typically, if you search for Mozart piano you want an album to match if Mozart is in the title or artist name of the album and piano is in the title of some track).

In addition, diacritics are ignored.