[3.2.13] Unlink Jadeite from $ROWAN_PROJECTS_HOME

[LisaAlmarode]

Per Dale, $ROWAN_PROJECTS_HOME is problematic in a multi-repository world. As it's been our rock and foundation for lo these many years, non-Dale people want to cling to it, rather than be set adrift. Initial discussions did not appear to be converging. This is posited to be out of scope for first release, but this issue to record the request and allow us to triage and prioritize.

This is related to #895 and may possibly be the same, but I think #895 is more limited in scope.