Remove extraneous vim configuration comments for ironic

Remove vim setting:

comment - # vim: tabstop=4 shiftwidth=4 softtabstop=4

at the top of source code files, except for files in
openstack/common.

Change-Id: Ie80f76f08e27b7f5f747227c4cca8d79ad98bec6
Partial-Bug: #1229324
Merge "Remove extraneous vim configuration comments for ironic"