Add PEP-484 type annotations to zerver/lib/.

zerver/lib/timeout.py

@@ -1,4 +1,5 @@
 from __future__ import absolute_import
+from typing import *
 
 import sys
 import time
@@ -33,8 +34,8 @@ def timeout(timeout, func, *args, **kwargs):
     class TimeoutThread(threading.Thread):
         def __init__(self):
             threading.Thread.__init__(self)
-            self.result = None
-            self.exc_info = None
+            self.result = None # type: Any
+            self.exc_info = None # type: Tuple[type, BaseException, Any]
 
             # Don't block the whole program from exiting
             # if this is the only thread left.