Add grunt dependencies and Gruntfile.js

Gruntfile.js

+module.exports = function(grunt) {
+    grunt.initConfig({
+        jshint: {
+        options: {
+            trailing: true
+        },
+        target: {
+            src : [
+                'converse.js',
+                'mock.js',
+                'main.js',
+                'tests_main.js',
+                'spec/*.js'
+            ]
+        }
+        }
+    });
+    grunt.loadNpmTasks('grunt-contrib-jshint');
+    grunt.registerTask('default', ['jshint']);
+};

package.json

@@ -25,5 +25,10 @@
   "license": "MIT",
   "bugs": {
     "url": "https://github.com/jcbrand/converse.js/issues"
+  },
+  "devDependencies": {
+    "grunt-cli": "~0.1.9",
+    "grunt": "~0.4.1",
+    "grunt-contrib-jshint": "~0.6.0"
   }
 }