[get_turns][relate] Handle spikes for L/L !opposite collinear and equal turns.

2 Turns are generated for a spike, one with operation_blocked the second one with operation_intersection.
relate_linear_linear is not working yet, for now it is only ensured that boundaries will not be checked for those turns, which would result with assert failure.
TODO: opposite collinear and equal, touches c/c and endpoints intersecting a spike + the adaptation of relate(L,L).