swagger_client uses PoolManager from urllib3. PoolManager keeps the
connection_pool_kw passed during the init time and uses the same later
while initiating HTTPSConnection. Existing implementation instantiates
RESTClientObject() at import time, without giving an option to pass
the security parameters, viz. key_file, ca_certs etc. So we needed to
change the way instantiation/initialization was happening.
(copied from I3b490bbb47eb5f961951708dabe6c1abfbcece4e)
Change-Id: I6df227bcd030cb8c374bc83bb44dfea980c893b3
c1d099e7f2