lang: Add simple README

lang: Clarify dispatch_call abort_msg

lang: Add a 'none' object to replace NULL uses

lang: Define Object as a void pointer

lang: Include types.h in object.h

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

This makes object a purely opaque type now

lang: Fix typo

lang: Check stack depth before accessing elements ...

I tested this code by hand, make sure to do the same if changing.

lang: Remove useless object cleanup checks ...

Once again we assume that we've gotten here correctly based on class data.

lang: Simplify number functions

lang: Check values since we're kind of testing anyway

lang: Add depth checks to compiler calls

lang: Add depth check bytecode

lang: Remove object_class forward declaration

lang: Set extra variables to NULL after dropping

lang: Always place VmState first in function calls

lang: Remove arg_count and rely on stack depth instead

lang: Hide VmState internals

lang: Add opaque types for Object and VmState

lang: Use stack offsets instead of pointers

lang: Handle vm_state creation in vm

lang: Switch to callee cleanup of non-return arguments ...

This simplifies calling things and will allow proper tail calls.

lang: Create vm state once in main

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: Clarify what skipping over ASCII and unknown OPs means

vm: Add stack pushing and popping

lang: Use vm_stack_get and set for OP_GET and OP_SET

lang: Rename vm.stack to vm.stack_next

lang: Add stack bases to vm

lang: Remove checks for obj->class_data ...

I have no idea how these could even trigger.