log: add colorized thread-specific logging
all: use log instead of print
book: fix error when trying to apply a trade for an order not in the book (happens because gateway fills are reported to the aggressor)
me: fix incorrect message type check for rejects
gateway: lengthen Messenger messages for safety; fix incorrect iteration over L when applying fills to pending cancels
messages: add book clear message to exchange feed when game ends, so we don't need to pass chess messages to get the right book
examples: fix case where there is no bid or ask
gui: disable logging within gui
examples: fix some bugs so that SIMM now works correctly
examples: working version of simple chess model
stockfish: interface to stockfish for use in fancy strategies
examples: add and use StockfishChessModel