Fix chat by setting g.timestamp.

The users online count recently added to wrappers.py:get_logged_in_user
uses g.timestamp for its calculations. This is primarily set in
__main__.py:before_request. However, chat has requests which do not
trigger @app.before_request. To resolve this, we now set g.timestamp
in the auth_required wrapper before calling get_logged_in_user().

I think this is safe in general; there's no particular harm to setting
the timestamp _more_ frequently.

files/helpers/wrappers.py

@@ -75,7 +75,7 @@ def auth_desired(f):
 def auth_required(f):
 
 	def wrapper(*args, **kwargs):
-
+		g.timestamp = int(time.time())
 		v = get_logged_in_user()
 		if not v: abort(401)