changing references of gluster to swiftonfile

As part of changing the project name from gluster-swift to swiftonfile, we are updating references of gluster to swiftonfile where it makes sense
Todo for later: During release (in future), may be it's a good idea to mimic Swift's release numbers. For example Swiftonfile 2.0.0 would be compatible with Swift 2.0.0. Just a thought.