Fix mixed up worker signal handling

Commit 81241907ffcf94517ffa14b8427205906b61b540 changed the signal
handling by switching the roles of `TERM` and `QUIT` for the arbiter
so that `TERM` is graceful and `QUIT` is not.

At the time, workers performed graceful shutdown on `QUIT` and quick
shutdown on `TERM` and `INT`. This behavior was also changed so that
`QUIT` (and `INT`) cause a quick shutdown and `TERM` is graceful.

However, the documentation incorrectly reversed the roles of the worker
signals and the arbiter was not updated to use the correct signals.

This commit fixes the documentation and the arbiter signals.

docs/source/signals.rst

@@ -35,8 +35,8 @@ Sending signals directly to the worker processes should not normally be
 needed.  If the master process is running, any exited worker will be
 automatically respawned.
 
-- **QUIT**, **INT**: Graceful shutdown
-- **TERM**: Quick shutdown
+- **QUIT**, **INT**: Quick shutdown
+- **TERM**: Graceful shutdown
 - **USR1**: Reopen the log files
 
 Reload the configuration

gunicorn/arbiter.py

@@ -336,9 +336,9 @@ class Arbiter(object):
         killed gracefully  (ie. trying to wait for the current connection)
         """
         self.LISTENERS = []
-        sig = signal.SIGQUIT
+        sig = signal.SIGTERM
         if not graceful:
-            sig = signal.SIGTERM
+            sig = signal.SIGQUIT
         limit = time.time() + self.cfg.graceful_timeout
         while self.WORKERS and time.time() < limit:
             self.kill_workers(sig)