some refactoring and cleanup...

Signed-off-by: Alex A. Naanou <alex.nanou@gmail.com>
added image pre-caching + minor revactoring...

Signed-off-by: Alex A. Naanou <alex.nanou@gmail.com>
more cleaning...

Signed-off-by: Alex A. Naanou <alex.nanou@gmail.com>