Fix IDT error # bug, add debug helper, continue debugging spawn_thread crash

The crash occurs after the newly-created stack is accessed, suggesting
that there is some bug in the paging code.
Begin tasking v3 rewrite
Begin multitasking refactor to support ring-3 TSS
Add flet1, flet, update reference
Document , and ,@
Add unquote-splice (,@)
Fix bug in error handling where __sub would be clobbered.
Fix LaTeX build
Add detailed error reporting, remove panics
Add Jmk for lisp reference, LaTeX CI
Add AND and OR
Add backquote/quasiquote (`).
Add Lisp reference document
Add tail call optimization, fix bug with vararg passing.
Fix segfault in Lisp when calling variadic function.

Originally a segfault could occur due to an issue with how arguments
were cleaned up after a variadic function call. After the function
call the following assembly was generated:

add esp, nargs

Where nargs was the number of arguments passed to the function. This
did not take in to account that for variadic functions, the last
several arguments are CONS'd into one argument, meaning that calling a
variadic function with <>1 variadic argument would result in a broken

Specifically this issue came up in the implementation of REDUCE, which
relied on the variadic FUNCALL.
Fix #PF in ext2 vfs
Mount EXT2 to VFS
Add ext2 VFS implementation
Abstract EXT2, add JMK Emacs integration
Add EXT2 insert into dirent