update

what has been done so far
- makefile added. So if you compile on Linux, you can remove all other
files, however keep *.cpp, *.c, *.h unit_circle.txt, makefile and
Colsamm folder intact
- data structure for matrix A and M is added.
- Calculation of Ah, Mh and k square are done. They are the same with
the reference results provided by the tutors

What need to be done:
- calculate inverse matrix to solve Ax = b. I was thinking to use red
black gauss seidel from the first assignment but don't know when to stop
the iterations.
- power iteration to calculate lambda