Fix Issue 1222 by changing the default Field of View for mouselook zoom

Smooth scroll changes the meaning of the numbers, unfortunately.. so for those who haven't figured out how to customize their mouselook zoom, this'll hafta do.
Also clarified the description of the debug.
SV-1222 #close Fixed up, will require a reset of the debug setting "zmm_mlfov", clean install, or just scroll to modify it.