add run_in_target.
add comments.
add vipple_zero functions.
single-quote -> double-quote
enable to set target ifname.
split failover-test.sh.
failover-test.sh -> failover-test_01.sh
split failover-test_01.sh.
add failover-test_02.sh.
add failover-test_11.sh.
add run-tests.sh.
add failover-test_12.sh.
add failover-test_13.sh.
add failover-test_21.sh.
add failover-test_22.sh.
Merge pull request #7 from hansode/vip-failover

Vip failover