Use correct scope for DEFAULT_RELOAD_TIME

Fixes runtime error:

    NameError: name 'DEFAULT_RELOAD_TIME' is not defined

Author: juergenhoetzel

livereload/handlers.py

@@ -69,7 +69,7 @@ def poll_tasks(cls):
         filepath, delay = cls.watcher.examine()
         if not filepath or delay == 'forever' or not cls.waiters:
             return
-        reload_time = DEFAULT_RELOAD_TIME
+        reload_time = LiveReloadHandler.DEFAULT_RELOAD_TIME
 
         if delay:
             reload_time = max(3 - delay, 1)