Fix tweet view icon size
Load newer tweets in timeline fragment
Remove unused SampleModel
Store current user info in shared preferences
Add redundant user screen name field to Tweet class

This is used for querying by screen name, until I figure out a way to do
it by querying for the User object.
Enable debugging of ActiveAndroid
Select user from DB by screen name
Load all timelines from DB if available
Update README for caching/loading of all timelines
Make getTimeline() function abstract

It should be implemented by each specific timeline type.