Module adapters

Helper types for trait impls.

Structs

• CoreWriteAsPartsWrite
• TryWriteableInfallibleAsWriteable
  A wrapper around TryWriteable that implements Writeable if TryWriteable::Error is Infallible.
• WriteableAsTryWriteableInfallible
  A wrapper around Writeable that implements TryWriteable with TryWriteable::Error set to Infallible.