Disable ServerSignature and Hide apache related infromation.

Change-Id: I9188ddb85988539087c922117bb9f53454b7507c

They dropped the cloudkitty-api command line[0], so we should add wsgi
support for cloudkitty-api.

[0]https://review.openstack.org/#/c/366043/

Change-Id: Ie34d4f2d5c303bbd7ac09a8ab9e8d9bdc763c57b
Closes-Bug: #1713879