ivy: allow 10000 (1e4) bits of floating-point precision
ivy: allow 10000 (1e4) bits of floating-point precision

Requires higher precision values of pi, e, and log2.
Turns out my saved value for log2 was wrong, but I used ivy to compute a new one,
and verified the computation was good to 10000 digits via
http://www.numberworld.org/digits/Log(2)/
so the first 3011 are fine.

That was fun.

beni55/ivy,postfix/ivy