move prerender hook back to original position

[myk002]

it's important that the prerender hook happens after the viewscreen render, otherwise the hook's rendering will be overwritten by the viewscreen

the naming might be confusing -- it's "prerender" as in "before the window blit", not as in "before the render to the screen buffer"

[Putnam3145]

Quickly tested, no noticeable issues at a glance--small enough change there shouldn't be in general