[libvirt] [RFC] Version numbers outside of releases

Our current practice when it comes to bumping the version number for libvirt is to do so immediately after a release, eg. right after 3.4.0 is released later today someone will push a commit that changes configure.ac to use 3.5.0 instead. As a consequence, builds made from master will always carry the release number of the *upcoming* release, so from a versioning point of view there is no way to tell eg. 3.4.0-rc2 or even the final 3.4.0 release apart from a random build made at a random time from master during 3.4.0's development cycle. In particular, when creating RPMs from a git clone, you'll end up having to use either 'dnf install' or 'dnf reinstall' depending on whether or not you already installed any build during the current development cycle. I suggest we change our habits slightly:   * right after X.Y.0 has been released, bump the version     number to X.Y.90;   * bump the version number to X.Y.91 for rc1, X.Y.92 for     rc2 and so on;   * only bump the version number to X.Y+1.0 as the release is     being prepared, then go back to the first step and move     on with development. This would make sure each step in the development cycle gets its own version number, and as a pleasant side effect you'll always be able to install newer builds using 'dnf install'. Comments welcome! :) --  Andrea Bolognani / Red Hat / Virtualization