Make socket.getservbyname test optional on socket module having that

attribute.  Jython does not have this function.

Closes SF patch #403667.

Lib/test/test_socket.py

@@ -83,10 +83,11 @@ for name in all_host_names:
 else:
     print 'FQDN not found'
 
-print socket.getservbyname('telnet', 'tcp')
-try:
+if hasattr(socket, 'getservbyname'):
+    print socket.getservbyname('telnet', 'tcp')
+    try:
         socket.getservbyname('telnet', 'udp')
-except socket.error:
+    except socket.error:
         pass