This change, in a backward-compatible way, allows users of the
native OVSDB library to pass in their own Idl factory function
where they can return any subclass of the Idl, any schema, and
and register whatever tables/columns they want. This way, we
do not have to keep up with changes to the upstream OVSDB Idl
library.
The Connection connection, schema_name, and idl_class arguments
are deprecated in favor of the idl_factory function.
Change-Id: I8133da63caa8937c4fce68eb2fbb73d36b894043