Play a night rain video

Summary:
Video source:

Vjatseslav Robtsenkov, Raindrops against the window in the night city, Las Palmas, 2016-11-05
https://commons.wikimedia.org/wiki/File:Raindrops_against_the_window_in_the_night_city,_Las_Palmas.webm
CC-0

This is a video file without soundtrack. Audio will be added later.

Test Plan: Tested on Chrome and Firefox

Reviewers: dereckson

Reviewed By: dereckson

Maniphest Tasks: T1354

Differential Revision: https://devcentral.nasqueron.org/D1387