Interactive supervisor mode

To ease the pain of debuggin I can now interact with the system through a
very simplistic terminal. Hopefully things can be tested more easily by activating
the piece through a simple command. The max characters for a command is 10.

To achieve this I have had to make the following changes.
- Changed IRQ to update a global status variable
- Added a standalone keyboard driver with getKey functions
- Changed the main kernel loop to display a prompt
- Added a strncmp function to the clib/string file

src/libc/include/string.h

@@ -1,3 +1,6 @@
 #pragma once
 #include <stddef.h>
 size_t strlen(const char* str);
+
+
+int strncmp ( const char* str1, const char* str2, size_t num );