Add an explanation of what the "description" field is for.
Boost maximum update size to 4KB.

This should allow for longer form updates if desired.
Fetch Google Analytics tracker when we fetch our tracker.

This will keep GA's numbers more in line with ours as currently the
sessions are expiring early on for long-running events.
Rename "editor" to "reporter" throughout the code.

Because the number of active streams is very low right now, migration of
the column names for reporter data can be done manually.