Basic text mode programming to be tested on Linux
along with a proper Makefile. Fixups and cleanup to
be done on Linux or throughout the day.

Features added in this commit:
* Main function that runs the kernel.
* Basic VGA/SVGA text mode.

Planned for future additions:
* Makefile
* Assembly & linker (very easy)
* GDT and x86 ISRs (maybe some ARM support in the future)