Implementation of the Line class

[raja-s]

So the Line class is implemented based on the equation: y = a x + b, where a is the slope of the line and b is its y-intercept. This is not ideal in my opinion. For example, in case of a vertical line, the slope is set to std::numeric_limits<double>::infinity() from the limits package.

A better implementation could be based on the equation: a x + b y + c = 0, which I think represents all orientations of a line in a cleaner way.

Another possibility to consider is to represent a line by a point and a vector, which is equivalent to a line parametrization:
x = x0 + vx t
y = y0 + vy t

As the whole implementation is still buggy, reimplementing the Line class and readapting all the other classes using it might help uncover bugs and hopefully fix them.