lib-rel-path is broken is some cases

Description

The above snippet is taken from:

https://ask.clojure.org/index.php/8743/not-a-relative-path-bug

Previously reported with other cases and examples:
https://github.com/emezeske/lein-cljsbuild/issues/490

Auditing this code it seems we should instead have a true relative path helper. Recently I wrote something like the following, perhaps it can be reused:

Environment

None

Assignee

Unassigned

Reporter

David Nolen

Labels

None

Approval

Triaged

Patch

None

Priority

Major
Configure