fix race condition where a transferring leg could be hungup on by the bridge partner from the previous bridge because of hangup held leg detection.  The leg which was hungup when held doesn't realize the other leg has already moved on from the bridge because it was transferred and is already on its way to connect to the new destination
FS-6289 --resolve regression from 1fba654845c8202bf84c58b203a3bc9624164c4e
FS-5886 --resolve add NDLB_broken_opus_sdp which must be set as a global variable in var.xml or switch.conf.xml to enable broken opus mode for back compat with counterpath mobile
FS-6287 this should either prevent the problem or spell out what is causing it. please test
FS-6168 --resolve
add sip_refer_to_params
FS-4441 FS-5461 --resolve

Conflicts:
	src/mod/applications/mod_conference/mod_conference.c
FS-5461 --resolve you tricked me I said make 1 patch with all of it

Conflicts:
	src/mod/applications/mod_conference/mod_conference.c
Send silent packets when idle with SRTP

Originally we did the same thing with SRTP that we do without SRTP,
which is to simply not send packets when e.g. sleep is called.

At commits d63323977fa611b141441f12af9a94ec19b5f829 and
5259814aee16ede974456490a79e8a98de1d6d2e we enabled sending silence
packets with comfort noise when SRTP is active.  We appear to have
done this for interop purposes; many devices can't handle gaps in the
stream of SRTP packets.

But our current comfort noise implementation doesn't take the codec
rate into account (FS-6291), so on 16kHz codecs the constant we chose
created an annoying level of static between sound file playback.

With this commit we preserve the sending of SRTP packets during idle
periods, but make those packets completely silent.

Thanks-to: Anthony Minessale <anthm@freeswitch.org>

FS-5053 --resolve