ignore endpoints with >1 adjacency in process rendering
ignore endpoints with >1 adjacency in process rendering

This eliminates the worst effects of #2665.

kinvolk/scope,weaveworks/scope,weaveworks/scope,alban/scope,alban/scope,kinvolk/scope,alban/scope,kinvolk/scope,alban/scope,weaveworks/scope,weaveworks/scope,kinvolk/scope,alban/scope,kinvolk/scope,kinvolk/scope,alban/scope,weaveworks/scope,weaveworks/scope