0751ee19d8
Nova allows deployers to configure the command line which is used to create a filesystem of a given type. This is frankly a little bit weird, but its also historical. Move this functionality to privsep, including doing a dance at startup to load config flags into privsep in a hopefully secure manner. Honestly, all of this code should be deprecated, but that's above my pay grade and would take time to do. Oh, and maybe deployers love it the way it is. Change-Id: Id8eeb21e10f98a448946f178c8c5a36e48c7cac6 blueprint: hurrah-for-privsep