Created header file for power management
Added outline of pm.c
Tracked outline of pm.c
Added assembly code to disable caching
Added enable_cache method and assembly
added function to store registers to stack.
added function to store registers to stack.
added function to store registers to stack.
Update pm.c
Added code to clean/flush data cache and instruction cache
Added clear_cache and enable_cache to cpu_idle and cpu_resume
added volatile keyword for registry access.
added volatile keyword for registry access
Reversed order of save_registers and clean_cache so as to not overwrite registers prematurely
Merge branch 'power_management'
Merge branch 'master' of https://github.com/rellermeyer/course_os