some changes to efficacy
difficulty influence on blasters

more waypoints allowed on higher difficulty, more likely to shoot in the first place.
refactor: one function for melee range validation.
fixes for some camera centering issues.
allow large units to go up levels where appropriate.

the reaper comes on wings of terror,
but we are safe, there's a pathfinding error,
the warboy sees, and disapproves,
and now the reaper slowly moves,
he climbs the ramp, and gains his entry,
we all lament; there was no sentry,
he eats my friends, he wounds me badly,
the warboy watches, laughing madly,
a warning, then; to all who'd listen,
next time you depart on a terror mission,
beware the reapers, the alien's toy,
their lack of AI has been fixed by Warboy.