Reimagine StdlibInt as InfiniInt.Stdlib

[oscbyspro]

This is the first part of (#96).

It adds the following modules:

• CoreIop (AdapterInteger)
• InfiniIntIop (InfiniInt.Stdlib)
• DoubleIntIop (DoubleInt.Stdlib)

It removes the following modules:

• StdlibIntKit (StdlibInt)

Additionally, you may note that:

• InfiniInt<T>.Stdlib automatically becomes generic over T
• InfiniInt<T> conforms to Interoperable in InfiniIntIop

[oscbyspro]

I'll add DoubleIntIop and DoubleInt<T>.Stdlib in a future patch.