Update instructions of installing k8s VIM
Update instructions of installing k8s VIM

The current `Kubernetes VIM installation` page has some
out-of-date instructions.

This patch replaces those out-of-date instructions with current
kubernetes manner, and fixes some other trivial mistakes
in the document.

Change-Id: I3d37aa215a9629f4ded92d0b4cb1b930658a2113
Signed-off-by: Masaki UENO <964a27e5f1f79c665e0f301a7856be652f67c7b7@hco.ntt.co.jp>

stackforge/tacker,openstack/tacker,openstack/tacker,stackforge/tacker,openstack/tacker