Convert binding_run to incremental processing.

Convert binding_run to incremental processing.

Ensure that the entire port binding table is processed
when chassis are added/removed or when get_local_iface_ids
finds new ports on the local vswitch.

Side effects:
  - Persist local_datapaths and patch_datapaths across runs so
    that changes to either can be used as a trigger to reset
    incremental flow processing.
  - Persist all_lports structure
  - Revert commit 9baaabfff3c7df014e9acbd4c68189b568552ca9
    (ovn: Fix localnet ports deletion and recreation sometimes
    after restart.) as these changes are not desirable once
    local_datatpath is persisted.

Signed-off-by: Ryan Moats <rmoats@us.ibm.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>