FormulaType.Name consistency

[MikeStall]

[1] For primitives, name in FormulaType.PrimitiveTypes should match FormulaType.ToString()

We should have a test to enforce this. One difference is Text vs. String.

The names in PrimitiveTypes should up in language spec for UDFs, so that should take precedence to ToString().

[2] Ideally, these would be definitive names and shared in serializer and other places.