This patch is a follow-up patch addressing the below comments
given on the commit 6ac31e0 :
* delete unused template files.
* Drop "config_drive" option and related code from resize instance
step because it need to show only for Launch Instance.
* grammer correction in the release note
Change-Id: I9ab52927fc6be31d491f010e5e3d9323ddd34e9e