matrix_client/room.py: Send audio and video using room objects
matrix_client/room.py: Send audio and video using room objects

send_content() in api allows us to send images, videos and audios.
Previously, only images could be sent using our room abstraction, now video
and audio can be sent as well.

Signed-off-by: Gal Pressman <810429a918df1a1db052ec005ef5cd915e26b6a4@gmail.com>

matrix-org/matrix-python-sdk