Bump JVM stack size to 4MB and eliminate tiered compilation.

This allows CLJS compilation to complete for complex go-pair forms.

See <emezeske/lein-cljsbuild#303> for more details.

project.clj

@@ -48,6 +48,7 @@
                                   [org.clojure/tools.nrepl "0.2.10"]
                                   [org.clojure/java.jdbc "0.6.2-alpha1"]
                                   [org.xerial/sqlite-jdbc "3.8.11.2"]]
+                   :jvm-opts ["-Xss4m"]
                    :repl-options {:nrepl-middleware [cemerick.piggieback/wrap-cljs-repl]}
                    :plugins      [[lein-cljsbuild "1.1.3"]
                                   [lein-doo "0.1.6"]]