NZ provider

[stueynz]

A substantial re-working of the code base allowing AU and NZ data models to be worked on independently.

The NZ model is very small, it only has a one data object - Provider (a generic data object that includes Schools, Early Childhood Education services, and Tertiary Education services). So it replaces SchoolInfo from the AU model. More data objects will be added during 2018.

This means:

• the bulk of Data-CommonTypes-Custom has been moved to separate domain based include files.
• the bulk of Data-CodeSets-Custom has been moved to separate domain based include files.
• there are a lot of <if intl="au"> statements removing the stuff we don't use (yet) from the NZ model.
• files that weren't well-formed XML files because they had multiple root elements, now have IncludeGroup as a root element; it makes things so much easier to validate while editing. Specgen codebase has been updated to take note of and ignore these IncludeGroup elements.
• SIF.input.schema.rnc has been seriously updated; element can contain lots of different elements.