* ref(connection-stats): use PropTypes package

* feat(connection-stats): display a summary of the connection quality

* feat(connection-indicator): show empty bars for interrupted connection

* feat(connection-indicator): change background color based on status

* feat(connection-indicator): implement automatic hiding on good connection

* fix(connection-indicator): explicitly set font size

Currently non-react code will set an icon size on ConnectionIndicator.
This doesn't work on initial call join in vertical filmstrip after
some changes to support hiding the indicator. The chosen fix is
passing in the icon size to mirror what would happe with full
filmstrip reactification.

* ref(connection-stats): rename statuses

* feat(connection-indicator): make hiding behavior configurable

The original implementation made the auto hiding of the indicator
configured in interfaceConfig.

* fix(connection-indicator): readd class expected by torture tests

* fix(connection-indicator): change connection quality display styling

Bold the connection summary in the stats popover so it stands out.
Change the summaries so there are only three--strong, nonoptimal,
poor.

* fix(connection-indicator): gray background on lost connection

* feat(icons): add new gsm bars icon

* feat(connection-indicator): use new 3-bar icon

* ref(icons): remove icon-connection and icon-connection-lost

Both have been replaced by icon-gsm-bars so they are not
being referenced anymore. Mobile looks to have connect-lost
as a separate icon in font-icons/jitsi.json.

Audio only mode can be used to save bandwidth. In this mode local video is muted
and last N is set to 0, thus disabling all remote video.

When this mode is enabled avatars are shown.