support junction = circular in all profiles, add additional tests

References:
- https://wiki.openstreetmap.org/wiki/Tag:junction%3Dcircular
- https://lists.openstreetmap.org/pipermail/tagging/2016-November/030520.html
- https://github.com/Project-OSRM/osrm-backend/issues/3361

profiles/bicycle.lua

@@ -221,9 +221,12 @@ function way_function (way, result)
   end
 
   -- roundabout handling
-  if junction and "roundabout" == junction then
+  if junction and ("roundabout" == junction) then
     result.roundabout = true
   end
+  if junction and ("circular" == junction) then
+    result.circular = true;
+  end
 
   -- speed
   local bridge_speed = bridge_speeds[bridge]
@@ -281,7 +284,7 @@ function way_function (way, result)
   else
     -- biking not allowed, maybe we can push our bike?
     -- essentially requires pedestrian profiling, for example foot=no mean we can't push a bike
-    if foot ~= 'no' and junction ~= "roundabout" then
+    if foot ~= 'no' and (junction ~= "roundabout" and junction ~= "circular") then
       if pedestrian_speeds[highway] then
         -- pedestrian-only ways and areas
         result.forward_speed = pedestrian_speeds[highway]
@@ -313,7 +316,7 @@ function way_function (way, result)
 
   -- direction
   local impliedOneway = false
-  if junction == "roundabout" or highway == "motorway" then
+  if junction == "roundabout" or junction == "circular" or highway == "motorway" then
     impliedOneway = true
   end
 
@@ -353,7 +356,7 @@ function way_function (way, result)
 
   -- pushing bikes
   if bicycle_speeds[highway] or pedestrian_speeds[highway] then
-    if foot ~= "no" and junction ~= "roundabout" then
+    if foot ~= "no" and junction ~= "roundabout" and junction ~= "circular" then
       if result.backward_mode == mode.inaccessible then
         result.backward_speed = walking_speed
         result.backward_mode = mode.pushing_bike