Got the GDT, IDT, and PIC working.
Lots of file changes today (Calhacks day two)
- VGA attributes can now be set using vgaSetAttribute
- you can now register an interrupt handler and call them
- PIC's are maskable, and you can set up lines for the hardware
- added some of string from libc to support functions
- Modified makefile so `make clean` wont kill the kernel.mod file too