Improve detail view

- Show count of Retweets and favorites
- expanded Tweet data model
Add icon set

- Icons for reply, retweet and favorite
Add call to action icons and tweet info

- within the different tweet list
- within the detail view
- Read only
- Shows if the user have retweeted or favorite the tweet.
Allow user to favorite a tweet from the list

- added custom selectors for favorite checkbox.
- add a listener that will make client call
- add methods to favorite and un-favorite the tweet.
- add a equals() method on the tweet class to allow to identify a tweet from the arrayAdapter
Fix re-adding the tweet on favorite click action
Remove unused code and add TODO
User can favorite/unfavorite tweet on detail view

- TODO: propagate this to relevant listviews to show up-to-date tweet info.
Add reply to post into client
Add reply-to-tweet funcitonality

- Reply to a tweet within the detail view as well as reply to a tweet within the ListView
Merge branch 'detail' into dev