Modify the 'include' of several files
Rename machine API and improve some CPU related functions
Move x86 implementation to a new directory and add minor improvements
Normalize function names of the task scheduler
Fixed name and visibility for some task scheduler functions.
Minor improvements in scheduler and trap prototypes and implementation
Improvements on trap interface and implementation.
Interface and implementation improvements for PIC (8259) and PIT
Add minimal support to load ELF32 executable files into memory