initrd/vfs work (does not compile)
vfs/initrd changes compile
vfs: file lookup via path strings
Fixed bug in vfs_get_dentry
made list.h independent of variable_queue.h
Cleaned up initrd_init() and finished initrd_read()

initrd_readdir() is implemented but untested.
vfs_{open,close,read} file operation wrappers
permanent initrd dir int boot/initrd/

Before this commit, initrd contents were just being pulled from
user/bin/. This meant you couldn't have any persistent files
across commits (user/bin/* get cleaned by make -C user/ clean).

Now the initial ramdisk pulls files from boot/initrd/* and user/bin/*
so that you can have permanent files in boot/initrd/ (like hello.txt).
updated README, added reference counters to vfs
reworked debug logging, added some loading code