Merge pull request #769 in FS/freeswitch from feature/FS-8836-support-ffmpeg-2.8-and-3.0-in-mod_av to master

* commit '1641fccd':
  FS-8836 fix deprecated warning on newer ffmpeg

* commit 'bdeacb1d':
  FS-8751 [Conference Play Video Total Time and Current Time]
  FS-8748 FS-8751 check current play_status
  FS-8748 track pdf total pages and current page
  FS-8754 add ability to read high quality PDF
  FS-8750 implement file_seek for video files

Merge pull request #677 in FS/freeswitch from ~JAONZE/freeswitch:bugfix/FS-8765-a-settings-menu-which-discards-expensive to master

* commit 'd3b4b492':
  Settings modal rework -> panel slider at top

Merge pull request #766 in FS/freeswitch from ~O_EMILIANO/freeswitch:bugfix/FS-8959-memory-leak to master

* commit 'f683c78a':
  FS-8959: [mod_av] fixed memory leak problem in encoding h264

FS-8959: [mod_av] fixed memory leak problem in encoding h264, fixed

FS-8959: [mod_av] fixed memory leak problem in encoding h264

FS-8970 - [verto_communicator] Setting 'none' for useSpeak/useMic/useCamera when calling a secondary canvas

Merge pull request #762 in FS/freeswitch from ~PIOTRGREGOR/freeswitch:bugfix/FS-8961-avmd-increase-robustness-of-variance to master

* commit '63a30499':
  FS-8961 Increase robustness of estimation

Merge pull request #761 in FS/freeswitch from ~PIOTRGREGOR/freeswitch:bugfix/FS-8960-avmd-set-buffer-position-to-beginning to master

* commit 'fce7cfee':
  FS-8960 Set buffer position to beginning on reset

Merge pull request #763 in FS/freeswitch from ~DCOLOMBO/freeswitch:bugfix/FS-8963-fix-label-status-call to master

* commit '7525bffc':
  FS-8963 - [verto_communicator]  fix label status call

Again, this shouldn't fix anything, but should make debugging easier.

FS-8312

Add optional requirement of consecutive streak
of estimations in SMA buffer. Fix definitions.
Add options to control debugging/printing.

* Remove unnecessary memset
* Narrow the scope of the global lock on session initialization
* Assert for couple of expected pointers

This won't fix anything, it's just maintenance clean up done
while investigating FS-8312.

Now buffer position is reset to 0.

FS-7800 should be able to call extra screens with same extension as the original and place the param conferenceCanvasID with the desired canvas id into the call params in the same place bandwidth prefs are added

FS-8957 #resolve [Video image sometimes blips on personal canvas mode when 1 participant is watching voh]