Remove old image.

Signed-off-by: Varun Ravishankar <vrdabomb@gmail.com>
Update .gitignore.

Signed-off-by: Varun Ravishankar <vrdabomb@gmail.com>
Optimize movie_stats.

Total time has gone down from ~5 minutes to 20 seconds. Optimizations done include minimizing number of joins, dropping all unnecessary columns ASAP, and performing operations on as few rows as possible.

Signed-off-by: Varun Ravishankar <vrdabomb@gmail.com>