hid, keyboard: pass USB keycode to keyboard service

add keycodes.h

hlib: add listClear function

stdio: add %p insert for padding

add fork system call

kernel await / fire event: add code to wait for specific event

usb: hlib: use "unsafe" direct event calls to work without strings

usb refactoring: no more xhci-specific code in main usb.h file

xhci refactoring: sperate out all xhci-related code to its own directory

use sleep function for xhci driver waiting for the controller to start

add sleep function to PIT driver

try initializing xhci hub

add system call to retrieve the physical location of a virutal address

add lspci user programm

move 'gets'-functionality to ioManager to simplify the shell source code

add await syscall

check if a message should be printed to the main vga screen by checking if any syscall in the 'syscall stack' is the foreground process

remove old log function, make \n mandatory for printing a new line

route the shell service to the vga output

rewrite general IO using an IO-manager

add system call to look up the names of functions

add basic stack tracing ability

rename service proivder to service function ...

now matches the documentation in the wiki

add formating print function

make malloc functions accessible to user mode programs

log to vga display

add system call to request memory ...

print hi to vga screen

use string identifiers for events ...

(some rework of the string saving system was required)

use stringmap for communication between processes

use saved strings for service interaction system calls