Remove CPItem in favour of individual item types
Add Field, Method, Interface, Attribute structs
Use Method struct when parsing
Start using generic item type for pool items
Use Item type and declare basic union
Add tagtostr; reintroduce enum for tag bytes
Implement tagtostr; interim parsing commit
Move hash adds to case sections
Build uthash.h
Use Ref to represent Method/Interface/Field
Use uint16_t instead of int for ids
Use HASH_ADD instead of _INT macro
Return a pointer from read_class
Return a pointer from read_class