Modifying search function, updating BackgroundT

Search function was not alerting user to subscriptions, nor updating
the MainActivity. It now
    * Doesn't exit prematurely if an item isn't found
    * Allows checking of multiple items

Along with this, the subscription will now show up on the MainActivity
page. A loading placeholder will be displayed and the image will
update dynamically.

Change-Id: Ide09413b6dab1c96413cfa35f2ed7370ef71e4e9