This makes the Serf inventory plugin use the `SERF_RPC_ADDR` and
`SERF_RPC_AUTH` environment variables that the `serf` command-line tool
already uses.

These can be used to get Serf data from a remote node instead of
requiring the ansible control host to be running a serf agent and to be
a member of the serf cluster.

Fixes #11132

Add serf inventory plugin

Add inventory plugin for [Serf](https://serfdom.io/).
Requires [`serfclient` Python module](https://pypi.python.org/pypi/serfclient).

Update syslog_json.py

localhost is better than locahost ;)

added vaultfile class for action and lookup plugin usage

should fix #11275

Allow AdHocCLI to be more flexible for overriding

aslo added comment clarifying why we do this

- moved check prompt/password functions to connection, make more senes there
- TODO: consider moving make_become to connection from connection_info
- removed executable param that was never overriden outside of connection info

fixed mixup with remote password vs become_password

- password prompt detection and incorrect passwrod detection to connection info
- sudoable flag to avoid become on none pe'able commands