We shall not only have a PropertyInfo. Most properties share common
behavior, that is, they have a type. Move the function pointers to
a NmcPropertyType structure, so that it can be reused for multiple
properties.
This promotes the idea that properties have a (limited) set of types
with some type specific behaviors. Contrary, to having each property
re-implement fully it's type. E.g. instead of having various property
re-define their full behavior as an "bool", have one property type
"bool" which can be attached to a property.