Some species don't fumble in shallow water.
Fix immediate_danger.
KoBe got a rune offline; rejoice.
Some tactics; still rough, but mostly serving as intended.

Known issues with current plan_tactical_step:
- quite slow!
- prioritization over other emergency actions might be bad
- should treat fast monsters at distance 2 as "ranged", probably
- should possibly ignore trivial monsters
- when multiple squares have equal value, should choose between them more
  intelligently
Fix bad logic when waiting for reaching enemies.
Use hand axe on DEBe (eoc).