hairloss, due to agvtool
The undocumented option -increment-minor-version is what I needed, such as in
agvtool bump -increment-minor-version
to bump the version from 0.0.1 to 0.0.2, instead of just 1 to 2 for instance.
I find it particularly inconvenient, that this tool updates the DYLIB_CURRENT_VERSION and well as the CURRENT_PROJECT_VERSION, when you could just set the DYLIB_CURRENT_VERSION like
in the project file