v1.2.15.2

Release v1.2.15.2

Core
 - Release v1.2.15.2
Use Case Manager API
 - ucm: add some traces for the config filenames
/Makefile.am
 - Makefile: remove dist-hook and remove tar option 'follow symlinks'
Error handler
 - error: fix the "return old snd_lib_error_set_handler() behaviour"
 - error: fix indendation in snd_lib_log_filter()
 - error: return old snd_lib_error_set_handler() behaviour

Signed-off-by: Jaroslav Kysela <perex@perex.cz>