FS-9634 #resolve [RTCP mux is always proposed on outbound channels even if rtcp_mux chan variable is 0]

 Log count of encoded FEC frames in debug mode

Improve spanish translations for verto communicator.

FS-9632 remove SWITCH_FILE_FLAG_VIDEO flag if we fail to receive video so we fall thru and record the audio only.  Previously it would just fail to function as expected.

More consistent with the naming in other events, eg
register and unregister.

Exposes Verto MediaStream objects via the onGranted() callback

aa

Some of the console.error messages generated in FSRTC aren't really
error-worthy, downgrading appropriately.

stream.onended is being removed in Chrome 54, update to
stream.oninactive

Conflicts:
	html5/verto/video_demo/js/verto-min.js

There was issue with certain endpoints that would lead to dropping
nearly every other RTP packet from the callee.

The scenario is as follows: the caller (bridged through FreeSWITCH)
offers codecs A and B with payload types X and Y, respectively.
The callee answers with codec B and payload type X.

The fix is to use the sender's expected payload type when checking
against the received RTP packet, rather than the receiver's.

FS-9653 #resolve freeswitch-meta-all-dbg should not depend on non-existant freeswitch-meta-lang-dbg %backport=1.6

FS-9642 #resolve do not limit time for real time threads with systemd. this causes systemd to randomly restart FreeSWITCH without notice as to why. %backport=1.6

FS-9648 #resolve [Conference avatar image gets stuck enabled when it uses the same image as video mute]

FS-9612 #resolve [RTCP-MUX wrongly enabled in cases where answer contains rtcp but offer didn't / remote addr not obtained in UDPTL mode] %backport=1.6

FS-9601: mod_opus:  make adjustable bitrate mutually exclusive with FEC enforcing on the decreasing trend,
add step calculation for bitrate adjustment, fix bug on context settings