* turned out the no-flight zone is also a no-climb-and-progress zone
* also changed it to not completely nullify velocity (otherwise cliffjumpers can get stuck in midair), just make sure dy is not negative
306cedbeb213
fixed several 'retina display' images and added a bunch more (though just from upscaling the normal ones; might be nice to have 'em redrawn at a real higher resolution)
