Update README.md

Author: aruntk

README.md

@@ -17,13 +17,13 @@ MwcMixin is a reactive meteor data source for polymer elements. Objective is to
 Add `mwc:mixin` package to your Meteor App.
 
 ```sh
-meteor add mwc:mixin@2.0.0-beta.3
+meteor add mwc:mixin@2.0.0-beta.4
 
 ```
 ### Method 2 - Using bower
 
 ```sh
-bower install mwc-mixin#2.0.0-beta.3 --save
+bower install mwc-mixin#2.0.0-beta.4 --save
 ```
 import mwc-mixin.html file.