Add analytics events for checking the usage

Realized that the session captured was only including popup.js so quickly added some more events. Now all the webpage impression and tap are captured but we can still add more meat by adding things what are the things that you are disabling/enabling vs the keywords they are entering. The code for analytics is just 10 lines long and lives here - https://github.com/bangarharshit/spot/blob/master/got-blockit/background.js#L201