RHEL > 7.4 support

[alankis]

Metadata:

• Operating System: RHEL 7.6
• Installation method: install.sh
• AWS CLI Version: aws-cli/1.16.122 Python/2.7.5 Linux/3.10.0-957.el7.x86_64 botocore/1.12.112

The public SSH keys aren't added to users on RHEL 7.5 and RHEL 7.6. What is the limitation? Maybe I can help with that.

[michaelwittig]

The solution is only tested with 7.4. If you use it with 7.5 or 7.6 you seem to be the first one trying this. PRs are welcomed.

[michaelwittig]

#143 seems also to try 7.6

[alankis]

Let us then leave this open I will try to add support for the RHEL > 7.4.