Fix term_print_dec(0)
Change term_print_hex to take a bool
Change #defines to an enum for FS_node types
Add TODO
Support negative ints in term_printf, add %u directive
Add %l directive
Not standard C (it should be a length modifier rather than a conversion
specifier), but I don't care for now
Change millisecond uptime counter to an unsigned long
Fix timer_notify
Use new %l directive, enable interrupts after initializing timer