Merge pull request #792 from waywardmonkeys/migrate-memory-management

Migrate memory management
[crt] Convert primitive_byte_allocate_filled and primitive_byte_allocate_filled_terminated to the new API.
[crt] Remove primitive_byte_allocate().
[crt] Remove instance_header_setter.

I want to remove things that use dylan_value*.
[crt] Just define the byte string and simple object vector structs.

Nothing used the macros to define other instances of the struct.
[crt] Improve type safety of debug-print.c
[crt] Update primitive_raw_as_string to use new MM APIs.
[crt] debug-print: Use more specific types for string data.

The real purpose of this change is to ensure that our build products
have debug info for the 'dylan_byte_string' typedef.