Using kernel/ramdisk makes no sense with local boot, we need a better
way. We already have an internal image_type instance parameter, let's
make it public.
Glance support will be added in the next patch.
Change-Id: I4ce5f7a2317d952f976194d2022328f4afbb0258
Currently it only contains (outdated) explanations how Ironic works.
Move them one level deeper and migrate the content relevant to users:
* Preparing instance images from the installation guide
* Deploying nodes from the standalone guide
Compatibility shims are provided for migrated pages.
Change-Id: I8468da377b7878eb3d1a61e6a6bcd4ac8a5f06d7