No limit on input numbers

[Istarnion]

Currently the parser has no limit on numbers in expressions, leaving us vulnerable to overflows and attacks that aim to exhaust all memory.
I don't deem it realistic to want more than 100k dice in a throw nor modifier, so I think that is a sensible cap.

Also consider using 64-bit integers for summing the result. Alternatively, report overflows as errors nicely.

[herrozerro]

Would you take a PR for this?

[Istarnion]

Sure!