Remove explicit dependency on amqplib

kombu already depends on amqp or amqplib depending on its
version, and no explicit access to amqplib exists in tuskar code.

Update logging config to list both amqp and amqplib, as kombu
will setup on or the other.

Change-Id: Ia0fc986fa59573a3936c44ed5a726ba366130301

requirements.txt

@@ -1,5 +1,4 @@
 
-amqplib>=0.6.1
 anyjson>=0.3.3
 argparse
 Babel>=1.3

tuskar/common/service.py

@@ -54,7 +54,8 @@ class PeriodicService(rpc_service.Service):
 def prepare_service(argv=[]):
     rpc.set_defaults(control_exchange='tuskar')
     cfg.set_defaults(log.log_opts,
-                     default_log_levels=['amqplib=WARN',
+                     default_log_levels=['amqp=WARN',
+                                         'amqplib=WARN',
                                          'qpid.messaging=INFO',
                                          'sqlalchemy=WARN',
                                          'keystoneclient=INFO',