This reverts commit b5b8e46.

This commit reverts the initial implementation of the
multi-node-multi-writer feature:
  commit: b5b8e46

It replaces that implementation with a more restrictive version that
only allows multi-node-multi-writer for volumes of type `block`

With this change there are no volume parameters required in the stoarge
class, we also fail any attempt to create a file based device with
multi-node-multi-write being specified, this way a user doesn't have to
wait until they try and do the publish before realizing it doesn't work.