check libraries differently when is required or is optional
set the default profiler for dlna_item_new
change default device values
create a list of profilers

instead to use only one profiler, it's possible to add more profilers.
dlna_set profiler becomes dlna_add_profiler.
the default profiler is always upnpav_profiler
VFS container id has to defined by the name of the container
dlna_item_new retrieves its original declaration.

It's mandatory dlna_add_profiler to use dlna_item_new with more than one profiler.
set the title to VFS container correctly
reorder the profilers list
set the media class for profiles of mpg123_profiler
add allowed values table for each State Variable of each services
add new structure for arguments of service's actions
CDS Browse action implement Allowed value
AVTS set allowed values for State variables