Heat rebalance, misc fixes

HEAT rebalanced:
-HEAT HE reduced, 22% (down from 33%) of a HE shell of same caliber.
-HE effect is correctly sized
-penetrator loses less energy on initial penetration, but loses massive
amounts on successive penetrations. End effect is layered armor is much
more effective at stopping penetrator.
-penetrator deals 13.2x more damage to crates, roughly equal to an AP
shell of the same caliber as the HEAT shell.
-penetrator deals 6.6x more damage to engines and fuel tanks, roughly
half of an AP shell.
-penetrator damage to everything else is unchanged.

Diesel explosions can be triggered by HE or HEAT.
HE blast radius and blast energy is now correctly displayed on the tool
and overlays.
Merge remote-tracking branch 'upstream/master'