Fix CLEAR_POINTS; add terminal conditional.

Add:
	makefile
		-add conditional to execute the engine in a gnome-terminal only when no
		SCRIPT_FILE argument is given, which is the only case that the shell
		will be activated.

	src/matrix.c
		-deallocate the sphere and torus matrices that addSphere() and
		addTorus() received from generateSphere() and generateTorus().

Fix:
	src/interpreter/interpreter.c
		-fix CLEAR_POINTS_CMD, which changed the value of the argument points
		Matrix_t pointer by setting it equal to a new matrix -- the change
		wouldn't be preserved because the pointer was itself an argument. Fix by
		passing in a pointer to the pointer.