Create bundles for autorelease post release tagging

Create bundles for autorelease post release tagging

Start treating all releases as possible release candadites which can be
released at any time the TSC approves a release. All autorelease jobs
will now contain an additional variable *next-release-tag* to signify
the next official release version.

See mailing list discussion thread here:
https://lists.opendaylight.org/pipermail/release/2016-April/006299.html

The release engineer can pull down the bundle files and run:

    git fetch /path/to/project.bundle
    git checkout FETCH_HEAD
    git tag -asm "OpenDaylight [release] release" release/[release]
    git push gerrit release/[release]

To push the build tags to Gerrit. This should cut back on the amount of
patches needing to be pushed to Gerrit for review by half and only the
x.y.z-SNAPSHOT patches need to be pushed.

Change-Id: I53bb95236e41c7e99a12c312e5158db51a9f4e67
Signed-off-by: Thanh Ha <thanh.ha@linuxfoundation.org>