Non-`Int` exponents

[AayushSabharwal]

Could the relevant types (Monomial, MonomialVector, Polynomial) be made parametric to allow non-Int exponents? Possibly even non-integer ones (acknowledging that non-integer exponents lose access to some algorithms)?

[blegat]

What would be the use case for this ? I try to keep the code as simple as possible and only add complication when there is a compelling use case :)