Add water image assets and POV-Ray source

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>
Port tunnel effect code

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>
Dots color adjustment

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>
Add README file

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>