chore(package): update react-router to version 2.7.0
chore(package): update react-router to version 2.7.0

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