Route over alternating oneways but not reversible ones, closes #2837.

- alternating: high frequency, route over them with penalty
- reversible: low frequency, do not route over them - time dependence

- http://wiki.openstreetmap.org/wiki/Tag:oneway%3Dreversible
- http://wiki.openstreetmap.org/wiki/Tag:oneway%3Dalternating

This distinction was made at the Elbe-Labe Meetup in Dresden, with
accompanying Wiki pages and tagging scheme. Thanks all involed!

- https://github.com/Project-OSRM/osrm-backend/issues/2837
- http://wiki.openstreetmap.org/wiki/Key:oneway

taginfo.json

@@ -44,10 +44,16 @@
             "value": "-1",
             "object_types": [ "way" ]
         },
+        {
+            "key": "oneway",
+            "value": "alternating",
+            "description": "high frequency reversible oneways are routed over taking the waiting period into account",
+            "object_types": [ "way" ]
+        },
         {
             "key": "oneway",
             "value": "reversible",
-            "description": "is marked as non-routable because of time-dependence",
+            "description": "low frequency reversible oneways are marked as non-routable because of time-dependence",
             "object_types": [ "way" ]
         },
         {