Adding _ to email regexp per stomlinson

lib/sanitize.js

@@ -19,7 +19,7 @@ var logger = require('./logging.js').logger;
 module.exports = function (value) {
   var isEmail = function() {
 
-    if (!value.toLowerCase().match(/^[\w.!#$%&'*+\-/=?\^`{|}~]+@[a-z\d-]+(\.[a-z\d-]+)+$/i))
+    if (!value.toLowerCase().match(/^[\w.!#$%&'*+\-/=?\^`{|}~]+@[a-z\d-_]+(\.[a-z\d-_]+)+$/i))
       throw "not a valid email";
   };