Fixes a crash: undefined method `[]' for nil:NilClass
that happens when a corrupt audio file is hit.

Pulled HTML5 locales on March 24, 2021

Enabled by default screenshare with audio (#11622)

screenshare: check if the user is still presenter after gDM resolves

If the presenter gets changed while the user kept the getDisplayMedia browser picker open, accepting the getDisplayMedia prompt might get the previous presenter´s client-side state inconsistent as if they were sharing. The screen sharing is a no-op though

This adds a check after gDM resolves to see whether the user is still the presenter; if they aren`t, just clean up the gDM stream and make it a full no op

screenshare: add rap processing for screen streams with audio (complements #11622)

Improve poll function

Fix userlist RTL/LTR for userlist when language is changed

audio: change default SDP format to Unified Plan

Making the default transition a bit earlier so that we can field trial it just to be sure enough it's safe.

Fix reactive issue with reconnection

Handle pad's events and Meteor's instances

Since Meteor was split in multiple process and events started to be
filtered by instances, all Etherpad's Redis events were being discarded.

Etherpad has a Redis' publisher plugin that is unaware of BigBlueButton's
existence. All the communication between them is kept simple with minimal
of internal data exchange. The concept of distincts subscribers at Meteor's
side broke part of this simplicity and, now, Etherpad has to know which
instance must receive it's messages. To provide such information I decided
to include Meteor's instance as part of the pad's id. Should look like:

 - [instanceId]padId for the shared notes
 - [instanceId]padId_cc_(locale) for the closed captions

With those changes the pad id generation made at the recording scripts had to
be re-done because there is no instance id available. Pad id is now recorded at
akka-apps and queried while archiving the shared notes.

Merge 2.2 into develop

Prevent logged out user to spam validateAuthToken

Default enable banner alert when user speaks with mic muted

This sets back the default value after fixes done in #11272 and #11268

If created, mutedalert will crash client when trying to access inputstream
which is not yet ready.
Fixes #11433

Avoid localhost at notes endpoint

Case insensitive typed poll responses grouping

Locales fetch rework

Retrieve guest user pre-join messages only when userId is available

Use 127.0.0.1 instead of localhost since Etherpad only listens for ipv4.

Move Raise Hand Functionality To Actions Bar Button