CLOUDSTACK-4257: [Automation] test_storage_motion test cases failed during with unexpected result in listStoragePool API call

Signed-off-by: Prasanna Santhanam <tsp@apache.org>
CLOUDSTACK-4257: Additional asserts for storage migration test

Test whether valid storage pools are listed and at least one pool is
available for migration.

Signed-off-by: Prasanna Santhanam <tsp@apache.org>
CLOUDSTACK-4356: Added code for checking empty host, skip the test if no empty host found

Signed-off-by: Prasanna Santhanam <tsp@apache.org>
(cherry picked from commit ac776608645a211328b7d5cb4865c798251aae87)
CLOUDSTACK-4199 Fixed redundant router fail over

When master router down, the back up router is entered into FAIL state
but it supposed to enter into master.
This issue is happening because the the enable_pubip.sh script triying to
ifdown and ifup the eth2 interface. Which is failed. So master.sh script got
failed. Fixed by doing ifdown force