lang: Handle all object allocation in object.c ...

This makes object a purely opaque type now

lang: Remove object_class forward declaration

lang: Always place VmState first in function calls

lang: Remove arg_count and rely on stack depth instead

lang: Add opaque types for Object and VmState

lang: Add back reference counting ...

The basic idea here is that we transfer ownership to and form the stack,
and clean up references that way.

lang: Drop reference counting, embrace leaking ...

I will add proper garbage collection later

lang: Replace args with a vm_state stack ...

This doesn't have any functional changes at the moment but will
aid in adding proper stack support in the future.

bytecode: Garbage collect the stack ...

This treats the stack itself as a place of references that needs to
be garbage collected and cleaned up. This will allow tail calls later.

lang: Return values in args ...

This allows multiple return values which makes things a lot easier.

lang: Remove symbols for now ...

Unfortunately until we can figure out how to build these at compile time we
have to get rid of them. Sad.

lang: Implement classes