Add a link in the info page to rate the application in the AppStore/Google Play store

Issue #84

IMPORTENT (Benny):
1. There is no support for iOS sinse I don't have one.. please add later on.
2. The function 'openMarket' appear twice by mistake (in InfoController.js & MarketController.js) - when you add the iOS support please delete one of them!
3. Checked in my Android - works fine.