Fix issues with :optimizations :advanced (#77)

* Fix index.js as generated with :optimizations :advanced.

Fix a ReferenceError exception being raised from index.js using
:optimizations :advanced.

* Fix single-file packaging.

Adding :optimizations :simple support in bd57679 seems to have broken
single-file packaging. :optimizations values (:none, :simple, :advanced) are
never namespace prefixed, so we were always using stuff-zip :default.

Author: alessandrod

plugin/resources/index-advanced.mustache

@@ -9,10 +9,10 @@ try {
 process.env.{{key}} = "{{value}}";
 {{/#env}}
 
-require("./{{output-to}}");
+var __CLJS_LAMBDA_NS_ROOT = require("./{{output-to}}");
 
 {{#module}}
 {{#function}}
-exports.{{export}} = {{js-name}};
+exports.{{export}} = __CLJS_LAMBDA_NS_ROOT.{{js-name}};
 {{/function}}
 {{/module}}

plugin/src/leiningen/cljs_lambda/zip_tedium.clj

@@ -55,17 +55,18 @@
         (when-not (.isDirectory file)
           (zip-entry zip-stream file path))))))
 
-(defmulti  stuff-zip (fn [_ {:keys [optimizations]} _] optimizations))
-
-(derive ::advanced ::single-file)
-(derive ::simple   ::single-file)
+(defmulti  stuff-zip
+  (fn [_ {:keys [optimizations]} _]
+    (if (#{:simple :advanced} optimizations)
+      :single-file
+      :default)))
 
 (defmethod stuff-zip :default [zip-stream {:keys [output-dir]} {:keys [index-path]}]
   (zip-entry zip-stream (io/file index-path) "index.js")
   (zip-below zip-stream (io/file output-dir))
   (zip-below zip-stream (io/file "node_modules")))
 
-(defmethod stuff-zip ::single-file [zip-stream {:keys [output-to source-map]} {:keys [index-path]}]
+(defmethod stuff-zip :single-file [zip-stream {:keys [output-to source-map]} {:keys [index-path]}]
   (zip-entry zip-stream (io/file index-path) "index.js")
   (zip-entry zip-stream (io/file output-to))
   (when (string? source-map)