fix: exit quickly on keyboard interrupt

When exiting roundup_server (issue was seen in use of roundup_demo)
using ^C, the keyboard interrupt message is generated but the
application didn't exit until the 60 second socket timeout is
complete.

This seems to be more of an issue with Windows.

With this change the socket is explicitly shut down telling the client
what's happening. Then the file descriptor is closed.

CHANGES.txt

@@ -54,6 +54,8 @@ Fixed:
   argument. Roles are indexed by lower case role name. So 'security
   User' and 'security user' should generate the same output. (John
   Rouillard from issue on mailing list by Chuck Cunningham)
+- make roundup-server exit more quickly on ^C. This seems to be
+  limited to windows.
 
 Features:
 

roundup/scripts/roundup_server.py

@@ -1167,6 +1167,12 @@ def run(port=undefined, success_message=None):
         httpd.serve_forever()
     except KeyboardInterrupt:
         print('Keyboard Interrupt: exiting')
+        try:
+            httpd.socket.shutdown(socket.SHUT_RDWR)
+        except OSError:
+            # forced shutdown can throw an error.
+            # we don't care as we are going away.
+            pass
         httpd.socket.close()