Added PIT support, sleep() exists!

src/kernel/main.c

@@ -3,6 +3,7 @@
 #include "isrs.h"
 #include "irq.h"
 #include "keyboard.h"
+#include "timer.h"
 #include "system.h"
 
 void main() {
@@ -13,6 +14,8 @@ void main() {
     sti();
 
     setupKeyboard();
+    setupTimer();
+    timerPhase(100); // 1 tick per 10ms
 
     clear(0x0f);
     print("kern.\n\n", 0x0f);