chore(package): update react-router to version 2.8.0
chore(package): update react-router to version 2.8.0

https://greenkeeper.io/
sarracini/activity-stream,AdamHillier/activity-stream,AdamHillier/activity-stream,sarracini/activity-stream,mozilla/activity-streams,mozilla/activity-stream,rlr/activity-streams,JaredKerim-Mozilla/activity-stream,JaredKerim-Mozilla/activity-stream,AdamHillier/activity-stream,mozilla/activity-stream,mozilla/activity-stream,rlr/activity-streams,Mardak/activity-stream,rlr/activity-streams,Mardak/activity-stream,sarracini/activity-stream,JaredKerim-Mozilla/activity-stream,mozilla/activity-streams,Mardak/activity-stream,AdamHillier/activity-stream,sarracini/activity-stream,mozilla/activity-stream,rlr/activity-streams,Mardak/activity-stream,JaredKerim-Mozilla/activity-stream