Remove redundant call to populateTimeline()

It gets called automatically by the EndlessScrollListener.
Add recording GIFs
Include launcher icon
Move various source files into subfolders
Make User and Tweet classes extend ActiveAndroid Model class
Add function to get tweets from SQL database
Fix call to get tweet uid

In the patch "Make User and Tweet classes extend ActiveAndroid Model class",
the getId() function was renamed to getUniqueId().
Factor out call to get twitter home timeline

This will use the SQL database as an alternative.
Save tweets to SQL database
Use tweet id of 0 as the NOP value
Edits for debug