Remove swiftkerbauth code

Swiftkerbauth is a generic auth middleware for Swift's proxy server.
It is not specific to swiftonfile (previously gluster-swift).

If development continues, the code can reside in a separate repo.

Change-Id: I2c6e805cd1a9eed6d42334352ceb66c4c5811b36
Signed-off-by: Prashanth Pai <ppai@redhat.com>
Merge "Remove swiftkerbauth code" into icehouse