Allow function overloading

[Strilanc]

When writing arithmetic functions, it seems common to have variants specialized to int, BigInt, and LittleEndian. It's confusing to have to remember different names for these functions, instead of just having one standard name with disambiguation via the type system.

[bettinaheim]

Thank you for your feedback! Yes, how to extend the functionality of generics has definitively been on our radar.

[bettinaheim]

We have temporarility moved this issue to the compiler repository for tracking.
This issue will migrate to the appropriate repository in the near future and will be processed there.
At this point we are not ready for contributions implementing this feature yet, but are of course always happy to see experimental implementations in a fork.

[alan-geller]

I'm going to transfer this issue to the qsharp-language repo, since that's now the proper place for language suggestions.