docs: added branch dashboard

Author: ethanneff

README.md

@@ -1113,6 +1113,8 @@
 
 # Additional Documentation
 
+- [Branch Dashboard](https://dashboard.branch.io/settings/link)
+
 - [Branch Docs](https://dev.branch.io/)
 
 - [Change Log](https://github.com/BranchMetrics/cordova-ionic-phonegap-branch-deep-linking/blob/master/CHANGELOG.md)