merge the changes of remod r413 + r414

http://code.google.com/p/remod-sauerbraten/source/detail?r=413 ;
http://code.google.com/p/remod-sauerbraten/source/detail?r=414
merge the changes of remod r415

http://code.google.com/p/remod-sauerbraten/source/detail?r=415
merge the changes of remod r416

http://code.google.com/p/remod-sauerbraten/source/detail?r=416
merge the changes of remod r417

http://code.google.com/p/remod-sauerbraten/source/detail?r=417