`leiningen.cljsbuild.config/compiler-global-dirs` leaks invalid `:externs` and `:libs`
Trying to solve http://dev.clojure.org/jira/browse/CLJS-994 revealed this issue.
Yeah, that's a vestige of #95, which coped with the lack of a library distribution story back in the day. It'll take a bit of work to excise the cruft.
I hoped a quick fix would work (just removing the offending default configuration), but doing so breaks a ton of tests (written using midje, which I'm loathe to touch).
Looked at this again, but just couldn't bring myself to nuke the relevant (useless) tests from orbit that would allow the elimination of the closure-js hack. Not a good idea to do so on the way out, IMO. :-(