Our current practice is that when we create a branch for version X, we bump the version number in the "master" branch to X+1. For example, we just created the 1.3.x branch, and bumped the version number in master to "1.4.0".
Proposal: we should instead use a version number like "1.4.0-devel" in the master branch. When the 1.4.x release branch is created, the first commit in that branch would switch to use the "1.4.0" version number. Meanwhile, master would be bumped to use "1.5.0-devel". The main benefit is to make it easier to distinguish official Mesos releases from snapshots that are taken from the master branch at some point during development. Note that according to SemVer, "1.4.0-devel" is considered to be "older" than "1.4.0", which is the behavior we'd want. Neil
