instances of lack of support for bigints

[gwhitney]

Describe the bug
We are starting to use mathjs 14 with bigint support in the Numberscope project, naturally shaking out some points concerning overall support for bigints. This issue collects four issues, for the sake of the PR for them I am about to file.

1. mathjs crashes if a bigint is used in a non-type-homogeneous instance of max or min.
2. if randomInt is called with bigint parameters, it returns a number, rather than a bigint.
3. randomInt cannot handle a range wider than the precision of a number (2^53).
4. log, log2, and log10 do not succeed on all bigint inputs.

To Reproduce

math.max(10n, 3, new BigNumber(7), fraction(3, 4))
math.randomInt(0n, 6n) // returns 0, 1, 2, 3, 4, or 5, not 0n, 1n, 2n, 3n, 4n, or 5n.
math.randomInt(0n, 10000000000000000n) // does not choose uniformly; many outputs impossible
math.log(10000000000000000n) // fails in implicit bigint->number conversion

[josdejong]

We are starting to use mathjs 14 with bigint support in the Numberscope project

Happy to hear that! I'll review your PR asap.