The manila-plugin interface was the cause of bug #1718152. This
is just to rebuild it and also migrate .testr.conf to .stestr.conf
Change-Id: Icd885409acdd788438857bcacdaac109b12cbad9
Related-Bug: #1718152
Depends-On: Ifc025d063d5fba5f2b8b20773b4a9543f883a0ea