New patch: MAN NL313CNG

MAN NL313CNG has received patch to v1.2
http://www.omnibussimulator.de/forum/index.php?page=Thread&threadID=43761

– Added shadows
– Generic NL 233 CNG suspension fix
– Retarder button actually switches the retarder off (button only exists in NL 313 CNG)
– Ramp button fix
– Dashboard screen measurements fix, currently wrong in all Generic versions due to a forgotten copy+paste