Move logic to open device selection outside of SettingsMenu so
it can be called independently by either SettingsMenu or by
the settings button itself if no other settings but devices will
be displayed.

Cleanup existing logic for displaying and updating device
selection settings in the settings menu. In its place
is a button to open the device selection modal.

Strings are not translated when opening the settings side panel. It was that we were creating settings panel html after i18n library had loaded and had translated the rest of the html.
The element selecting the current language was also not translated, which end up with no selection in the UI for the current language.

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

Removes storing avatarURL in localstorage and retrieving it.

This reverts commit 93648f361b.