v0.1-rc.7

• Add support for simultaneous requests from different consumers
• Add producer url to logs
• Fix double start for RTSP source (possible fix for #47 #144)
• Fix STUN candidate in IPv6 format #148
• Fix wrong RTSP H264 profile for some cameras #155
• Fix GetMedias for producer in reconnect state #111
• Speedup container building using Golang cross-building #150 @skrashevich