GTE Genetic Turmit Evolver

Use selection to evolve turmits. Turmit's behavior is defined by an expression
in reverse polish notation using an infinite loop stack and avoiding arithmetic
errors.


Exemple :
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# Evolve a pool of random generated turmit (with prog expr of size 5) the pool
# contains 15 turmits and only the best 1/5 is kept. The "best" is evaluated
# after 30000 steps and on an average of 3 runs. 2 threads will be used and
# a log with all expr and there fractdim will be written in gte.log
python3 -m gte evolve --threads 2 -L gte.log -p 15 -D 5 --steps 30000 -R 3 --prog-size 5

# Fast evolve from scratch
python3 -m gte evolve --threads 1 -L gte.log -p 16 -D 4 -R 5 -T 3 --steps 2000 -x 256 -y 256 -P '0' -E

# Generate an image of 40000 steps of 10 turmits in gte.png
python3 -m gte generate -o gte.png --steps 40000 -x 1024 -y 1024 -T 10 -P '0x982A POP 0xAE9D R & +'