Put the tanks on a diet.
take no chances with the data patch

people don't seem to want to download the data patch themselves, so i guess
we need to take a more aggressive attitude toward these annoying little map
bugs. this one fixes the skyranger cockpit and the walls on the lightning.
shave off some semicolons

aesthetics.
method for marking tiles as "dangerous" to the AI
danger zone checking for alien AI behaviour

as well as a small refactor to check target validity, incorporating
danger zone checks.
even guided missiles drift

but they do so by a fixed amount, based on faction, of all things.
chryssalids only infect humans
fix some stuff when intercepting with multiple landing craft
fix accuracy adjustment
fix for some melee and medkit related stuff

make them both use validMeleeRange, and make validMeleeRange store the
position of the tile a valid melee target was found in. this avoids the
need for deriving the location later, removing the need for copy/pasted
defective code and making everything look all neat and shiny
extend the last waypoint line.