Ignore H302 - bug 1398472

Due to bug 1398472 ignore H302 (import only modules).

Change-Id: I777dabe622f96dc6f0e2c6df605fd86ad8a7387c
Related-Bug: 1398472
drop developer support for OS X

Due to an increasing number of incompatibilities between Keystone
dependencies and OS X (openssl, ldap, eventlet), this drops support for
Keystone development on OS X.

Change-Id: I3c8b3b165487e460a06b43dd44d701995fa3b655
Merge "drop developer support for OS X"