mrhyde: fix replacement warning

from pull request dribnet#8

note that I have not yet updated the clojure dependencies as doing so breaks
the array functions in the unit tests.

updated cljs and clojure version

Empty map / extend_js test / latest cljsbuild+cljs deps

incremental 0.5.2 release with (better) Array.reverse/map/forEach

now runs wheelbarrow example in a non-embarassing way.

Added support for Array.filter with test

First standalone release of mrhyde.