Rust implementation works with 32bit float numbers

[EndrII]

Some time ago i detected that the rust implementation have absolutely different noise result of C implementation,

It turns out the issue wasn't just minor differences in the algorithm's implementation, but also the fact that the algorithm generates low-precision 32-bit numbers, which is extremely detrimental to the use of this library.

See https://github.com/KdotJPG/OpenSimplex2/blob/master/rust/smooth.rs#L47

Please switch to 64-bit numbers.