Allow setting maxsize for PoolManager

Author: yuvipanda

configuration.py

@@ -30,9 +30,7 @@
 
 class ConfigurationObject(object):
     """
-    NOTE: This class is auto generated by the swagger code generator program.
-    Ref: https://github.com/swagger-api/swagger-codegen
-    Do not edit the class manually.
+    Configuration options for RESTClientObject
     """
 
     def __init__(self):
@@ -85,6 +83,12 @@ def __init__(self):
         # Set this to True/False to enable/disable SSL hostname verification.
         self.assert_hostname = None
 
+        # urllib3 connection pool's maximum number of connections saved
+        # per pool. Increasing this is useful for cases when you are
+        # making a lot of possibly parallel requests to the same host,
+        # which is often the case here.
+        self.connection_pool_maxsize = 1
+
     @property
     def logger_file(self):
         """

rest.py

@@ -97,6 +97,7 @@ def __init__(self, pools_size=4, config=configuration):
             'ca_certs': ca_certs,
             'cert_file': cert_file,
             'key_file': key_file,
+            'maxsize': config.connection_pool_maxsize,
         }
 
         if config.assert_hostname is not None: