Fix null/undefined issue

Author: paf31

.gitignore

@@ -1,3 +1,4 @@
+.psci*
 bower_components/
 output/
 

bower.json

@@ -16,5 +16,9 @@
   "dependencies": {
     "purescript-maybe": "^0.3.0",
     "purescript-functions": "^0.1.0"
-  }
+  },
+  "repository": {                                                          
+    "type": "git",                                                         
+    "url": "git://github.com/paf31/purescript-nullable.git"            
+  } 
 }

src/Data/Nullable.js

@@ -3,7 +3,7 @@
 
 // module Data.Nullable
 
-exports.$$null = null;
+exports["null"] = null;
 
 exports.nullable = function(a, r, f) {
     return a == null ? r : f(a);