Storlets/Release Branch Creation

This is a temporary procedure till we are "Big Teneted"


 * 1) In two different patches:
 * 2) pin the dependencies versions (Swift and Keystone) in tox.ini and in devstack localrc.sample
 * 3) In tox.ini place in the appropriate line:
 * 4) git+git://github.com/openstack/swift.git@2.7.0 < The version of the stable release
 * 5) In localrc.sample add e.g.:
 * 6) SWIFT_BRANCH=stable/ocata
 * 7) KEYSTONE_BRANCH=stable/ocata
 * 8) Update CHANGELOG with the tag for the release, and the Release notes.
 * 9) Once the above patches are approved create and push the above-mentioned release tag, this will initiate the PyPI jobs. Make sure your .gitconfig is up-to-date with e.g. the gpg signingkey entry.
 * 10) git tag -m "stable/newton tag" -s 0.3.0
 * 11) git push gerrit 0.3.0
 * 12) Create the branch
 * 13) git checkout -b stable/newton
 * 14) git push gerrit stable/newton
 * 15) Update the openstack release repo (currently we are in an independent release cycle format)
 * 16) checkout https://github.com/openstack/releases.git
 * 17) Edit deliverables/_independent/storlets.yaml
 * 18) Add the release branch and version in the existing format.
 * 19) The hash should reflect the hash of the latest commit done before creating the branch point (the CHANGELOG commit)
 * 20) TODO: Do we need to update this in case of a backport??
 * 21) On master undo the dependencies version pinning
 * 22) If a backport is required checkout the branch and cherry-pick the backport commit:
 * 23) git checkout stable/newton
 * 24) git cherry-pick
 * 25) git review stable/newton