Hard math to fix issue #571. Well, not really hard math, just checking if vector is in opposite direction and trait that as a special case when removing rope dividing point (this could only happens when rope sticks to land outline, so this basically fixes a bug in another bug).

oups

fix compilation with clang. fixes issue #553 - thanks to julien for reporting and to drew for the first part of the fix

at vatten's request. make resurrection always resurrect at least 1 hp out of kindness to noobs who can't be bothered to read tooltips