Support CLJS namespace aliasing

[danielcompton]

A new feature of CLJS (unreleased at time of writing) lets you write clojure.test and have the CLJS compiler fall back to cljs.test if it can't find a ClojureScript/CLJC file called clojure.test: http://blog.fikesfarm.com/posts/2016-07-03-clojurescript-clojure-namespace-aliasing.html

This means that a CLJC namespace requiring [clojure.test :as t] should resolve valid in CLJS mode and CLJ mode.

[mtruyens]

This is now official in Clojurescript 1.9.198: https://groups.google.com/forum/#!topic/clojure/-uG5kDcSEIs

[cursive-ide]

Yes, I'm going to get this into a 1.4.0 EAP release soon.

[cursive-ide]

Sadly, I've had to bump this to the next EAP build due to the subtleties involved.