bigbuckbunny: Add 480p, 720p and 1080p movies

This provides a recipe to install the movies in the rootfs; these
allow for people to make demo images which carry the movies for show.

These recipes are based on Angstrom ones. Thanks by their base work.

Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>