Add build, installation and removal process for kernel module

[alichtman]

Will close #12 when complete. Still need to add:

• [x] argparse interface for setup.py
• [x] loading of the kernel module

Related notes:

$ sudo insmod rootkit.ko # Load this module into the kernel.
$ lsmod # Display loaded kernel modules
$ sudo rmmod rootkit.ko # Unload rootkit.