* Support native_type for tables when using the C++ object API.
If native_type is specified on a table:
- No object API struct type is generated.
- The object API refers to the table by its native_type.
- UnPack and Create<TableName> methods are declared but not defined; as they
must be user-provided.
* Add tests for native_type on tables.
* Add documentation for native_type on tables.
rboullard
cosmith-nvidia