glance requires pyOpenSSL>=0.11

glance uses  OpenSSL.crypto.sign() and OpenSSL.crypto.verify(), which are new in pyOpenSSL 0.11
Fix global requirement first, then glance will use it

Change-Id: Id3b06be8ee203c3d15ccc2d846df0d0d8c4145ea
Partial-Bug: #1268966
Merge "glance requires pyOpenSSL>=0.11"