Added pucks.worlds.ai.world3 and made distance torroidal.
Fixed bugs related to toroidal nature of world.
Version bump.
Added torpedoes, shooters, and pucks.worlds.ai.world4.

Also tweaked physics, including allowance for higher acceleration after
collisions (to prevent torpedoes from going through walls).
Shooter-related updates.

Changed shooter color.
Added shooters to pucks.worlds.dev.world1.
Version bump.
Avoid calculating neighbors of stones.
Version bump.
Removed automatic memory merge from physics.

If a merge is desired then the proposal function can propose that
:memory be (merge (:memory p) ...). The automatic merging would have
made forgetting difficult.
Reverted memory merge; added state-based darters.

Determined that requiring full memory merging in proposal functions is
too onerous; arbitrate-proposals will now (again) merge proposed memory
map with previous memory map; values can be easily forgotten, although
not keys. Darters demonstrate agents with state-based control
architecture. The pucks.worlds.ai.world5 world demonstrates darters.
Version bump.
Fixed indentation of relativize-position.
Strip memory from sensed agents.
Changed doc/intro to point to the readme.
Fixed incorrect memory stripping + more

Stripping of memory from sensed agents was done incorrectly; fixed this
and also strip neighbors, overlaps, and inventory. Also, partial
implementation of gates and keys
Tweaks to post-collision physics, more work on gates.
Gates, keys, and abbreviate-embedded-agents

Implemented gates and keys, and the transaction handling necessary to
support these. Also provided a abbreviate-embedded-agents function to
keep printing of agents reasonable, for example, when clicking in the
GUI.
Chests require requests + transaction bug-fixes.
Tweaked physics for head-on, equal velocity collisions.

Head-on, equal velocity collisions would previously cause agents to
stick together. Added minimum for velocity in collision resolution.
Memory/inventory trades implemented.

Demonstrated in pucks.worlds.dev.world8,