4 bytes: 4cc
File type idendifier

20 bytes: TypeInfoHeader
4       | 4              | 2             | 2          | 4              | 4
Version | Base Type Hash | Base Type Idx | Type Count | Type Data Size | Member Data Size

TypeDataSize bytes: TypeDefs
MemberDataSize bytes: Member data names, indexed from TypeDef

// todo: enum table for upgrading strings?

xxx bytes: actual data, Load/Save with BaseType
