Eliminate Clojurescript clone replacement warning

`cljs.core` [defines](https://github.com/clojure/clojurescript/blob/master/src/cljs/cljs/core.cljs#L466) `clone`, so the Clojurescript 0.0-2138 compiler throws the following warning when including data.cljs:
```
WARNING: clone already refers to: /clone being replaced by: wagjo.data.array/clone at line 105 resources/public/js/out/wagjo/data/array.cljs
````