Nightbus vs. daytime traffic stations / Needs: Function to block parts of RBLs

[burnoutberni]

One should be able to add RBLs, but then block certain vehicles from the RBL.

Problem at Metalab: Closest daytime traffic station on lines D, 1 and 71 in the direction of Schottentor is Stadiongasse/Parlament, but for night lines running along the Ringstraße it's Burgtheater/Rathausplatz, which is also a stop for daytime traffic, only further away. We currently only have Burgtheater/Rathausplatz added to catch all lines, day- and nighttime. We should actually filter away all daytime traffic at Burgtheater/Rathausplatz and add Stadiongasse/Parlament for that purpose.

Even more tricky are night lines with different courses on weekdays/weekends. This affects line N38 at Metalab, which stops at Burgtheater/Rathausplatz during the week, but starts at Schottentor on weekends. If we're lucky this is actually reflected with the different RBLs of Schottentor, but one has to check the API on a weekday night to find that out.

[burnoutberni]

Should be fixed now with 3a3d723

Someone should check the weekday/weekend thing, but I'll open another issue for that.