refactor: rename 'Topology' to 'Routes'

Since that is what it is. By contrast, when the docs talk about
topology they actually refer to the peer connectivity graph.

site/troubleshooting.md

@@ -69,7 +69,7 @@ Peer 7a:16:dd:5b:83:de (v31) (UID 13151318985609435078)
    -> 7a:f4:56:87:76:3b [37.157.33.76:7195]
 Peer 7a:f4:56:87:76:3b (v1) (UID 6913268221365110570)
    -> 7a:16:dd:5b:83:de [191.235.147.190:6783]
-Topology:
+Routes:
 unicast:
 7a:f4:56:87:76:3b -> 00:00:00:00:00:00
 7a:16:dd:5b:83:de -> 7a:16:dd:5b:83:de
@@ -105,7 +105,7 @@ number of the connection. In the above example, the local router has
 connected to its peer using address 191.235.147.190:6783, and its peer
 sees the same connection as coming from 37.157.33.76:7195.
 
-The 'Topology' section summarised the information for deciding how to
+The 'Routes' section summarised the information for deciding how to
 route packets between peers, which is mostly of interest when the
 weave network is not fully connected.  See the
 [architecture documentation](https://raw.githubusercontent.com/zettio/weave/master/docs/architecture.txt)