pixmap: Make it possible to draw drop shadows as part of image decoding
Get rid of PIXMAP_RGB24

24bit RGB bitmaps is not supported by any HW so it always needs
additional conversion. Pointless since we can do when rescaling anyway
Fix bug in JPEG/JFIF memory reader
Use JPEG (instead of PNG) for storing thumbnails in cache
glw: Allow chain of tokens to be used as default args
Fix broken sorting when displaying a TV show season
Make sure metadata scanner stops when we leave a directory

Also fix possible crashes related to those occations

Fixes #1601
More finegrained locking around thumbnail generator
Avoid some insane stack allocation in XML parser
Add support for sorting on filename and date when browsing over UPNP