Start work on fire ants.

Tweak armor mechanics and display.  Add the concept of natural armor (at
least for now).

Other changes: Adjust log messages for confusion (following ToME's example)
and messages for intermediate effects from unseen sources.
Finish implementing flame slash.

Assign default DamageType colors.  Clean up damage type color and message
handling a bit.
Heat Carapace talent.

Fix various bugs with resistances reducing damage below 0, display of
resistances in character sheet, Fire Slash as used by fire ants.
Burden of the Ant talent.  Working encumbrance.
Burning Hand talent (minus particle effects)

Tweak some message formatting - try to use "himself" where appropriate,
avoid letting the source see passive effects on unseen targets.

Fix duration display in GameDisplay.tempEffectText.
Particle effects for Burning Hand
First attempt at Hive Mind talent.

Very rough initial implementation of party members and summoning.
Minor tweaks
Merge branch 'fire-ants'