Revert "[jenkins] - use a new method to determine the branch name by ignoring the pr ref_spec - thx to theuni for figuring that out"

This reverts commit afb5a6998c0c0a191e88ae53671df79fc00d55b2.

It resulted in "undefined" branch name. Stick with the old method until someone decides its not working for all cases. Sry TheUni - but theory proved wrong ... ;)
[musicdb] fix for duplicates when mixing musicbrainz & non-musicbrainz artists
[musicdb] don't clean music library on scan (fix for deleting music when source is offline)
Merge pull request #3090 from night199uk/musicfixes

[musicdb] Music DB fixes for a few of the recently reported issues
[depends] - fix compilation of python26 when compiling for android on osx host
AE: add planar formats to end of enum, some other code relies on the order
AudioEngine: Add AE_IS_PLANAR(x) macro
AE: WASAPI - fix AddPackets for the case of provided frames are less than buffer size
ActiveAE: engage transcode for stereo if upmix is selected
ActiveAE: flush engine on flush stream if only one stream is active
ActiveAE: check for error during playback
dvdplayer: flush audio on close stream in case of nowait
ActiveAE: faster flushing of stream
AE: WASAPI - fix GetDelay
ActiveAE: do not pause stream when flushing it
AE: adapt limiter to planar formats
ActiveAE: fix volume amplification
AESinkOSS: Implement Drain()
ActiveAE: make sure GetDalay returns no negative values
AESinkOSS: Make sink usable in blocking mode