- easier support for non-mandatory functions.

  In some boundary conditions it can be desirable to support
  additional functions, but not necessarily require them. Make this
  easier to support with a Function1, PatchFunction1 NewIfPresent()
  selector.

- support for compatibility lookups

- harmonize branching logic and error handling between Function1 and
  PatchFunction1.

ENH: refactor a base class for Function1, PatchFunction1

- includes base characteristics, patch or scalar information

ENH: additional creation macros

- makeConcreteFunction1, makeConcretePatchFunction1Type for adding a
  non-templated function into the correct templated selection table.
  makeScalarPatchFunction1 for similarity with makeScalarFunction1