* Adding a help button on top of the chat, that links to the online documentation on frama.io.
* Replaced github.io documentation links by frama.io documentation.
* Adding links to the documentation in the diagnostic tool.
Replacing webpack by ESBuild for client code compilation (as in the
official quickstart plugin).
So we can remove deprecated webpack dependencies.
Note: webpack is still used for ConverseJS build.
This may be removed soon.
Related to issue #122.
From now on, webchat can only be activated for local videos.
It will never be displayed on remote videos.
This is because an incompatibility with a new feature (webchat per channel).
Moreover this feature was very limited: the webchat was not shared with the remote instance (this will probably be achieved in a future release).
* init some shared functions (videoHasWebchat, parseConfigUUIDs)
* api/room: checking that video has live enabled
* fix promise handling in initChat function
* removing some 'use strict' that are no more necessary in typescript
