Add support for ansible-core 2.11

[msafadieh]

The ssh connector plugins added the new following variables: sshpass_prompt, ssh_transfer_method, and timeout. This causes the sshjail plugin to fail with the following error.

An exception occurred during task execution. To see the full traceback, use -vvv. The error was: KeyError: 'Requested entry (plugin_type: connection plugin: sshjail setting: ssh_transfer_me
thod ) was not defined in configuration.'                                                                                                                                                    
nginx.shams | FAILED! => {                                                                                                                                                                   
    "msg": "Unexpected failure during module execution.",                                                                                                                                    
    "stdout": ""                                                                                                                                                                             
} 

This PR fixes the bug by adding the new variables to sshjail's DOCUMENTATION string.

[Follpvosten]

I'd be very interested in getting this merged. This issue is stopping me from using the connection plugin.

[austinhyde]

Thanks a ton for the patch! Sorry it took so long to get it reviewed and merged. I did hit one snag, which is that apparently retries got renamed to connection_retries at some point and core 2.11 insists on it being present...

After doing some testing, it looks like updating that dict entry works all the way back to ansible 2.10, so I'll call that a success.

I'll merge this, then apply that rename real fast.