f4d26add25
This fix tries to address the issue raised in 24596 where it was not possible to join as manager only (`--availability=drain`). This fix adds a new flag `--availability` to `swarm join`. Related documentation has been updated. An integration test has been added. NOTE: Additional pull request for swarmkit and engine-api will be created separately. This fix fixes 24596. Signed-off-by: Yong Tang <yong.tang.github@outlook.com>