* Avoid destroying calls until they are hidden from the UI
We often want calls to exist even when no more participants are left in the MatrixRTC session. So, we should avoid destroying calls as long as they're being presented in the UI; this means that the user has an intent to either join the call or continue looking at an error screen, and we shouldn't interrupt that interaction.
The RoomViewStore is now what takes care of creating and destroying calls, rather than the CallView. In general it seems kinda impossible to safely create and destroy model objects from React lifecycle hooks, so moving this responsibility to a store seemed appropriate and resolves existing issues with calls in React strict mode.
* Wait for a close action before closing a call
This creates a distinction between the user hanging up and the widget being ready to close, which is useful for allowing Element Call to show error screens when disconnected from the call, for example.
* Don't expect a 'close' action in video rooms
These use the returnToLobby option and are expected to remain visible when the user leaves the call.
* Add commercial licence and update config files
* Update license in headers
* Revert "Update license in headers"
This reverts commit 7ed7949485.
* Update only spdx id
* Remove LicenseRef- from package.json
LicenseRef- no longer allowed in npm v3 package.json
This fixes the warning in the logs and failing build check.
