Bootloader: Locate the kernel's data segment and clear it.

This was a constant source of stupid bugs and I kept postponing it because
I wasn't in the mood to write assembly code. Until now! :^)

Kernel/ProcessGUI.cpp

@@ -12,11 +12,6 @@
 
 void Process::initialize_gui_statics()
 {
-    Font::initialize();
-    WSMessageLoop::initialize();
-    WSWindowManager::initialize();
-    WSScreen::initialize();
-
     new WSMessageLoop;
 }