Added TODO file

This will keep track of things that need to be handled, but at the
moment I don't feel like handling.
The start of an APIC module

For now it checks to see if an APIC exists and then creates a virtual->physical mapping. It then uses the mapping to read a few of the APICs registers to make sure things got mapped correctly.
Enable the APIC and enable interrupts

Added a call to apic_init() inside interrupts/init.c
Added a call to interrupts_init() inside kmain.c
Merge branch 'master' of https://github.com/wlitwin/Base64