Added list.h
    - Now using proper linked list implementation
    - Updated references
Updated list implementation to avoid segfault
Cleaned IO benchmark
Using for_each_entry macro in cpu benchmark
Removed vestigial statements from old implementation in cpu
Added free_list macro
Working towards nanosleep
CPU benchmark now uses nanosleep
TODO:
    - Fix bug causing repeat to not work
    - Clean up flow
Commented buggy repeat option