refactor: drop simplejson requirement

After much benchmarking, it was decided that it is preferable to
remove the simplejson dependency. This comes with the caveat that json
handling is slower on Python<=2.6, but faster on Python>2.7, including
Python 3 and pypy.

The recommendation moving forward is to deploy Marconi on Python>2.7.

Change-Id: If7a9380bd32023ec973fd2f267255723aaa49306

marconi/queues/transport/utils.py

@@ -13,7 +13,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import simplejson as json
+import json
 
 
 class MalformedJSON(ValueError):

marconi/queues/transport/validation.py

@@ -13,10 +13,10 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import json
 import re
 
 from oslo.config import cfg
-import simplejson as json
 
 
 _TRANSPORT_LIMITS_OPTIONS = [

requirements.txt

@@ -9,7 +9,6 @@ msgpack-python
 pymongo>=2.4
 python-keystoneclient>=0.3.2
 python-memcached
-simplejson>=2.0.9
 WebOb>=1.2.3,<1.3
 stevedore>=0.10
 six