Force stop the router would release all the resources it used, but router may
still running. Add a column "stop_pending" in the database, and stop it when the
router come back.
Admin would able to choose to force destroy such router, then recover the
network using restartNetwork command with cleanup=false.
Part 2
commit 797839360c65cd348d2eb20630521177ab0919de
bug 9154: redundant virtual router
commit 8ff7f230204d4d3a7a4adee75523a9a84f4276fe
bug 9154: Replace domain_router.is_master with domain_router.redundant_state in DB
commit 230b99e9e0b152648f1dd2a5eab6f22315b8e7b4
bug 9154: Add redundant state to DomainRouterResponse
commit ccefb5ff5e83d713798a347c99bce1a0d04b4317
bug 9154: Add router fault state report
commit 7a3090378f9785caecf741b70554f6ea17c41764
bug 9154: Send alert if found two virtual routers in master state
commit 66831056e4bf27665871bccd24e6159071564847
bug 9154: Code clean up
commit bf3f58a85741fa7118bd848a42d8b21baa4478d4
bug 9154: Add isRedundantRouter to DomainRouterResponse