change tilecode handling so  '-' and '0' both mean empty
add start of offline tileset explorer
mods to tilecode alphabet so we can map tilesets to integers
worked on it
added backtrack variant which wont backtrack past the initial seed tile
added choose-best-of-n-runs and evaluate-tileset-all-seeds
removed unwanted zeros from random tilecode distribution
write tilings to database
enumerated all fully self compatible tiles with up to 3 connections
removed unneded imports
work in progress
changed container from list to vector
updated tilesets
refactor to remove dependence on facecode.clj which was mostly early experiments
work on improving state management, purification
more refactoring, purification, breakage
refactoring towards removing global state
more refactoring, state management
Delete game.clj-bak
fixed problem with cache-dead-nbhood