Drop hashlib/hmac from pip-requires.
Drop hashlib/hmac from pip-requires.

Python 2.5+ has hashlib.

Python 2.2+ has hmac.

As such there really is no need to have these in pip-requires.

Change-Id: Iaa7f6a6f2db4c5283608c320680da98ae400098f

darren-wang/ksc,klmitch/python-keystoneclient,metacloud/python-keystoneclient,citrix-openstack-build/python-keystoneclient,alexpilotti/python-keystoneclient,alexpilotti/python-keystoneclient,klmitch/python-keystoneclient,sdpp/python-keystoneclient,citrix-openstack-build/python-keystoneclient,jamielennox/python-keystoneclient,Mercador/python-keystoneclient,ging/python-keystoneclient,sdpp/python-keystoneclient,ntt-sic/python-keystoneclient,jamielennox/python-keystoneclient,jamielennox/python-keystoneclient,citrix-openstack-build/python-keystoneclient,ntt-sic/python-keystoneclient,magic0704/python-keystoneclient,darren-wang/ksc,ging/python-keystoneclient,magic0704/python-keystoneclient,ntt-sic/python-keystoneclient,metacloud/python-keystoneclient,Mercador/python-keystoneclient