Repopulate router, port and floating ip related caches

Repopulate router, port and floating ip related caches
These caches can create a problem in a cluster environment
where node goes down and rejoin the cluster. All the caches
will be clear on restart, and if newly join node become master
instance, it can break the functionality. This patch is re-populating
all the required caches

Change-Id: I2f7b6f8f8871eb7c6fc7c96d9e4e121adbf5c950
Signed-off-by: Anil Vishnoi <vishnoianil@gmail.com>