lang: Add None objects to the language

lang: Add booleans

lang: Replace func with dynamically compiled module ...

I did some tweaking to the style of the generated bytecode but otherwise
this is basically merging func.c in to compile.py. Seems to work for now.

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

lang: Fix typo

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

lang: Always place VmState first in function calls

lang: Add opaque types for Object and VmState

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.

vm: Add stack pushing and popping

lang: Rename vm.stack to vm.stack_next

lang: Add stack bases to vm

lang: Drop reference counting, embrace leaking ...

I will add proper garbage collection later

lang: Wrap stack functions

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.

lang: Fix arg counts to include return value

lang: Pass NULL values to calls first instead of later ...

This looks a bit awful right now but will be important later on
when we add proper support for calls in bytecode.

lang: Remove OP_DROP since we clean up when returning anyway

lang: Put return value as new args ...

This avoids the dispatch having to free values.

lang: Add OP_DROP to bytecode

lang: Introduce func that just returns 1234

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

lang: Replace symbol table with FNV hash ...

I don't want to deal with writing cross-platform thread wrappers at the
moment so we shall just switch to using hashing for symbols.

This isn't great as we can't iterate through existing symbols and it's
possible to collide these if you really want to, but it shall do.

lang: Split in to library and executable

lang: Run clang-format