fix fuzzy_stripey missing segment when dy > 0

also makes it try harder to approach the target weight, by default

vacation.p8

@@ -517,7 +517,7 @@ fuzzy = {
  p = 0xffff,
  n = 0,
  interval = 3,
- tries = 2,
+ tries = 4,
 }
 mknew(fuzzy, function(x)
  local p = (x.p or fuzzy.p) & 0xffff
@@ -578,7 +578,7 @@ function fuzzy_stripey:update()
  fz.tries = self.tries
  self.y += self.dy
  if (self.y <= -self.gap) self.y += self.gap
- if (self.y >= self.gap) self.y -= self.gap
+ if (self.y >= 0) self.y -= self.gap
  fz:update()
 end