GRIM: If ActorLookAt is called with an actor as the target, look towards the actor's head instead of their origin. Fixes #887
MISC: Add copyright notice from glm
MISC: Add copyright notice from glm
MISC: Add COPYING.MIT
EMI: Enable backface culling. Fixes #900
Merge pull request #921 from Akz-/emi-contract-fix

EMI: Enable backface culling. Fixes #900
Merge pull request #891 from Akz-/grim-lookat-fix

GRIM: If ActorLookAt is called with an actor as the target, look towards...
GRIM/EMI: Fix bridge height check.
GRIM/EMI: Remove bridge length check.
MATH: Return false in intersectLine2d if lines do not intersect.
GRIM/EMI: Always walk towards the target position in a straight line if possible.
GRIM/EMI: The walk destination may reside in multiple sectors, so don't choose a single end sector.

This fixes Elaine walking through Guybrush at the end of the first cutscene in the set gme.