Reduant constants?

[jakub791]

There are constants like EXP_LIMIT, NUNBER_EXP_MIN, LAYER_DOWN which I think aren't meant to be changed by people using the library (like some sort of configuration)?
If that's true then it might be better to remove them and just use the values directly in internal code.

[Patashu]

Or like documentation-for-programmers or something.

Could go either way on this one. Never thought about it super hard.