removes local.html

On mobile we got the extra step of overriding the option and always set it to
true.

- Expose an api on Filmstrip to hide the remote videos container, which does so
  by adding a class
- Modify listeners for user join, leave, share video to call the api
- Hide the container when there is 1 or fewer remote participants
- Always show the container if self view is in focus
- Show the container if the number of remote thumbnails does not match the count
  of remote participants, such as the case of sharing a video

In its current implementation, the VideoStatusLabel shows HD based on peer
connection stats. These stats will be available on temasys browsers soon but
will remain unavailable on Firefox, which does not collect height/width stats.
To support VideoStatusLabel showing cross-browser, move the high-definition
detection out of stat sniffing and instead check the video element itself using
an interval in LargeVideoManager. (An interval was used because the temasys
video object does not support the onresize event.) Also, add a cleanup path from
conference.web to LargeVideoManager to remove the interval.

Starting with Firefox 51 the extension is no longer mandatory, so make sure the
feature is not desabled by default.

This config option is not used anymore.

Starting with firefox 52, no extension is required for screensharing.
See https://wiki.mozilla.org/Screensharing

The feature has been replaced so the option no longer applies.

It makes for a bad first-time experience for users, since the desktop sharing
button will be visible, but it will never work.

Also get rid of the now deprecated `desktopSharingChromeMethod` option.

Enable ESLint on jitsi-meet with the same configuration and the same
goals as in lib-jitsi-meet.

When enabled after hanging up redirect to close page, if needed feedback will be displayed.

In conjunction with corresponding commits in lib-jitsi-meet and jicofo
this enables adaptive simulcast whenever simulcast is enabled.

order to not change existing behaviour (without changes to config.js).

order to not change existing behaviour (without changes to config.js).

of forcing one or the other in automated tests).

Renames some fields in config.js.

now fully supported by jitsi-videobridge and all browsers which we
support (and if we need to enable them conditionally because of browser
compatibility in the future, we should do it based on run-time browser
detection.)