Basic potential class created

It only works with python numpy array, but the core idea remains.
Doesn't work

Looks like someone is messing with the heap! This does not work,
should be debugged properly and also put the table as a class, as
it used to be
Still doesn't work, now all set in c code directly

I don't know what's the problem, but to make some tests I worked
on the c code, inputing a dummy LUT so I can make it look like
the python bindings. I think there is some pointer that is being
stepped on.
Refactored potentila class. No work still

I just changed place of potential, so it has its own class.
Eventually, it should have a function so that potential.V(r) returns
the potential and potential.F(r) returns the force directly, or
something like this. Encapsulating is better!

But making it work is best
Little modifications to pull master from repo
Removed empty files
Add comment and information in files
Merge branch 'master' of https://github.com/JLeitmotiv/ljmd-c
Added How to Use
Updated how to use
Modified how to use
c-code works!
Python bindings succesfully created!

Now we should try to merge it
Merge branch 'potential'

Conflicts:
	python/md_classes.py
	src/ljmd.c
	src/mdsys.h
It doesn't work yet, just checking main.py
Merge works now, it's jony's time
main.py file refactored
Finally GUI supports the potentials