FS-8354 #resolve [G722 audio issues with mod_conference after fab43547]

FS-8891 #resolve [T38 fax fails between 2 freeswitch boxes, with high cpu usage (comparison overflow?)]

FS-8884: add --disable-libyuv and --disable-libvpx configure args to disable building these libraries

* commit '6334e1ce':
  FS-8864 #resolve [Improve video file playback]

* commit '4827e221':
  FS-8871: Fixed encoding "&" and "<" symbols in vanilla config

Merge pull request #692 in FS/freeswitch from ~DCOLOMBO/freeswitch:bugfix/FS-8792-video-quality-combo-box-doesn-t-apply to master

* commit 'c6921959':
  FS-8792: apply video resolution on combobox video quality changes

FS-8867: do hidden visibility on vpx as we don't want symbols leaking out of libfreeswitch, and we get relocation error on a vpx symbol anyways

FS-8867: build using in tree libvpx, vpx no longer optional and does not use system libvpx due to issues with having to update it frequently conflicting with system libraries, now we link to the static in tree version instead.  Also, mod_vpx is now a core module instead of a loadable module, so mod_vpx.so will no longer be built

FS-8867: build using in tree libyuv to match required version and not impact system ones that are never sufficient version

add libvpx 89cc6825 (matching current chrome canary) from repo https://chromium.googlesource.com/webm/libvpx

FS-8856 - [mod_callcenter] Inserting member as a new one when restoring action fails because our agent_dispatch_thread removed the members just before we tried to update him.