Default RNG using the Xoroshiro128plus algorithm. This is a robust RNG with 128 bits of state. Note that low bits have less entropy than higher bits: use sign test to derive random booleans (or randomBool()), and use right shifts (or random()) to derive smaller values (as opposed to modulo). Adapted from http://vigna.di.unimi.it/xorshift/xoroshiro128plus.c
Create an instance using a 64 bit seed. The seed is used to initialize a 64-bit RNG from which two state values are extracted.
Returns a random number within the range from start (inclusive) to end (exclusive).
Alter the random number generator in a deterministic way depending on its argument. Used for generating random functions: the generated function will take its argument, perturb the generator, and use that to generate the return value.