Comparison between points

[hroncok]

Currently, it is not possible to compare two points.

a = Point(0, 0)
b = Point(0, 0)
a == b
> False

It would be useful to have this functionality.

def __richcmp__(Point self, Point other, int operation):
    if operation == 2:
        return self.x == other.x and self.y == other.y
    elif operation ==3:
        return self.x != other.x or self.y != other.y
    else:
        ...

More info at: http://docs.cython.org/src/userguide/special_methods.html#rich-comparisons

I can write it, after my previous PR is merged.