profile: move all stream chain code to profile.c from htsp_service.c
profile: added unique id (service or channel) to profile chains
profile/subscription: use profile chain everywhere, add profile refcounting
mpegts: allow to remove dvb service
dvb get string: allow to override charset when auto detection fails, fixes #2407
profile: fixed copy-and-paste error
htsp server: fixed wrong condition (profile_chain_work)
webui: changed rights for playlist, dvrfile, fixes #2409

- /dvrfile requires (advanced) streaming or recorder rights
- /play requires (advanced) streaming or recorder rights
- /playlist requires rights depending on functionality
  - dvr playlists requires recording rights
  - channel and tags playlist requires streaming rights
muxer libav: review again the h264 filter payload free code
service mapper: fix the abort due to missing streaming target initialization
webui: the /play redirector - add more user-agent direct streaming, fixes #2412

- 'VLC/'
- 'MPlayer '
- 'Lavf/' (ffmpeg, libav)
- shoutcastsource (some media players?)
webui: /play - direct streaming for no user-agent providers, remove VLC for direct

(note vlc is fine with playlists and shows the correct title for matroska)
config: fix prefer_picon name in the storage structure, fixes #2413
profile: fix timeshift creation for htsp profile, add more timeshift logs
HELP: Update image for help

-Configuration > General
-Channel/EPG > Channels
WEBUI: Changed icon

-Clean icon image cache
-Reset Icon
tsfix: fix pts/dts for all streams (including teletext)
timeshift: for initial pts value, scan more packets (now 6)