Add lock mechanism for the concurrent requests
Add lock mechanism for the concurrent requests

This patch adds the file-based lock mechanism for setup and teardown to
prevent the multiple concurrent access to the API server, which leads
the creation of the duplicated resources.

Signed-off-by: Taku Fukushima <48ddf7139da17a0278f1f27e611ac6b9304f94b2@midokura.com>

midonet/midonet-kubernetes-prototype,tfukushima/midonet-kubernetes,tfukushima/midonet-kubernetes,midonet/midonet-kubernetes-prototype