Add version checks and a VERSION file to releases.
This extends the release script to check the supplied version
argument against the one found in the toplevel CMakeLists.txt.
This also extends the script to create a VERSION file with the
Ceres version, Ceres ABI version, and commit corresponding to the
tarball.
For example, the VERSION file might like this:
version 1.3.0
abi_version 1.3.0
commit c161a9d0b800dc93a711cb1fc04af9cf86f2968b
Change-Id: Idc407d5dcbe9bf3d854f5e393a57b365f10ed0fc
1 file changed
