* per-package-version hint files (e.g. named <pvr>.hint, or /.setup.hint inside tar file)
* automatically vault stuff which has dropped out of setup.ini
* more than 2 versions possible (and automatically vault 'old' versions, where we have some mechanism to explicity say what is old)
* automatically suppress 'empty source' packages with no deps from setup.ini ?
* run more often, option to not do anything if no uploads (to avoid reading the release area if we don't need to), lockfile to avoid colliding runs
* work out some way to package it as a replacement for genini
* use irkerd to report when calm failed due to an error?
* upload a hash at the same time as package, and pass that through to setup.ini
