* Add support for sending user-defined encrypted to-device messages
This is a port of the same change from the robertlong/group-call branch.
* Fix tests
* Expose the method in MatrixClient
* Fix a code smell
* Fix types
* Test the MatrixClient method
* Fix some types in Crypto test suite
* Test the Crypto method
* Fix tests
* Upgrade matrix-mock-request
* Move useRealTimers to afterEach