Proposing fix for Issue #4324; adding support for su in connection plugins ssh, ssh_alt

Fixes for ssh_alt support, adding in references to in_data where appropriate
Make sudo and su command line arguments mutually exclusive
Enable su support in paramkio; disable su support in fireball, local, accelerate, chroot, jail, funcd connection plugins
Resolve rebase conflicts
Ensure playbook support for su params
Hostvars support for su
Merge pull request #5325 from angstwad/add-su-support

Proposing fix for Issue #4324; adding support for su