include config option to control homedir removal

[packetfairy]

Operating System: Linux
AWS CLI Version: aws-cli/1.11.13 Python/3.5.2 Linux/4.13.0-1006-gcp botocore/1.4.70

userdel -r is a bit aggressive. It would be nice to have a config option to control homedir removal on account deletion.

[michaelwittig]

we have a config USERADD_ARGS, so I suggest we just add something called USERDEL_ARGS?

[KusabiSensei]

That's a trivial addition in my uninstall shell script that's on my fork.
https://github.com/KusabiSensei/aws-ec2-ssh/blob/feature/uninstall/uninstall.sh

I'm not sure what the best way to control that for packaged installations (rpm and deb) are.