Catch permission error thrown by firefox elements
Build sjcl.js
Merge remote-tracking branch 'deckar01/fix-mouse-event-errors'

Conflicts:
	sjcl.js Not resolved - deleted, will rebuild after improvement
Also when reading position of mouse event fails, the time is still
useable.

Timestamp is in milliseconds, assuming it has 2 bits of entropy instead
of 0 for mouse and accelerometer