Fix syntax of bullet image reference in styles.css

Signed-off-by: Tony Butler <tonyjbutler@gmail.com>
Update version.php for Moodle 2.6.x release

Signed-off-by: Tony Butler <tonyjbutler@gmail.com>
Increment build number for 2.6.1 release

Signed-off-by: Tony Butler <tonyjbutler@gmail.com>