Weakly connected component: Relationship orientation and weightProperty are redundant

[tomasonjo]

The relationship orientation plays no role with the wcc algorithm, whichever option you pick, the result should be the same. Also, weight property doesn't influence results in any case if we don't add a threshold option, which is not available in the menu. I would also rename the default write property from unionFind to wcc_component or something, now that we have moved away from naming the algorithm unionFind.