Sub pycrypto with cryptography test_cert_resources
Sub pycrypto with cryptography test_cert_resources

pycrypto is no longer maintained [1]. This patch rewrites functions
using pycrypto and replaces them with the cryptography equivalent for
the test_cert_resources.py file

[1] http://lists.openstack.org/pipermail/openstack-dev/2017-March/113568

Change-Id: I345c411abd2cf405cfc0a9163b4b60daca8d66c5

openstack/barbican,openstack/barbican