Add more math evaluation tasks

[jordane95]

Regarding math evaluation, it seems that the current repo only supports gsm8k, math, two problem solving benchmarks. There are more fantastic evaluation suites being proposed recently, like using PoT, python code interpreter, formal proof, etc. Maybe we could integrate tasks from this repo(https://github.com/ZubinGou/math-evaluation-harness) for more comprehensive evaluation?

[haileyschoelkopf]

We are very interested in including more math evaluation tasks. The linked repo is a good reference--If there are other specific tasks you would like definitely drop links to them here.