Give players an extra turn before drowning to grabbing monsters

Players now have two turns to react to a monster in water grabbing them
and drowning them instead of one.  After a monster "swings itself around
you!" it "pulls you towards the water!" and only then "drowns you..."

Having two turns to react to drowning attacks allows more tactical
options than one turn, and having two messages makes it much less likely
that either message will go unnoticed.

If the player is life-saved from drowning, the grabbing monster won't
let go, but the player will still get the extra turn before the monster
drowns them again.