Support Arrays in browserify conf

`exclude` and `ignore` would not accept an Array of paths before, since
`Browserify.prototype.exclude/ignore` was expecting a single file as
argument.

lib/builder-browserify.js

@@ -39,7 +39,11 @@ function configure(bundler, cfg) {
         if (type === 'transform' && typeof o[type] === 'object') {
             bundler[type](o[type].name, _.omit(o[type], 'name'));
         } else {
-            bundler[type](o[type], _.omit(o, type));
+            var values = o[type];
+            if (!Array.isArray(values)) values = [values];
+            values.forEach(function (value) {
+                bundler[type](value, _.omit(o, type));
+            });
         }
     }
 }