Add const qualifier to pointers in data_write_* functions
Add error macros that work better with Lua functions
Load/save ModelShape from/to an AlStream, not a filename
Add *bytesRead param to stream read() to detect EOF
Add optional name field to AlStream
Can init read-only memory streams on the stack
Load scripts using streams
Update scone files with new sources
Use #define and not `const int` to keep gcc happy