Make singleton.js the entry point via npm

Author: benvinegar

package.json

@@ -11,7 +11,7 @@
     "type": "git",
     "url": "git://github.com/getsentry/raven-js.git"
   },
-  "main": "dist/raven.js",
+  "main": "src/singleton.js",
   "devDependencies": {
     "chai": "~1.8.1",
     "grunt": "^0.4.5",

src/singleton.js

@@ -1,3 +1,9 @@
+/**
+ * Enforces a single instance of the Raven client, and the
+ * main entry point for Raven. If you are a consumer of the
+ * Raven library, you SHOULD load this file (vs raven.js).
+ **/
+
 'use strict';
 
 var RavenConstructor = require('./raven');