included user input for missing vars, disabling passwordAuth and enab…

[17Halbe]

Hi there,
I changed the script to my liking and thought you might be interested. I removed the necessity to use commandline options and inserted user input demands for the not provided (and neccessary) options.
Additionally added the option to modify the sshd_config file on the host to disallow passwordAuthentication and allow PubkeyAuthentication if desired. It also checks if those config changes would be able to be made due to permission restrictions.
It furthermore tries to get the currently used sshd_config file (ps aux | grep ...)
Some documentation changed and the information about a daemon reload was added additionally with a final login check.

Hope that was all and understandable. ;) Thanks for your work and sorry for the hasty PR, I'm in a hurry!

[centic9]

Thanks for the proposed changes. I will merge at least some of it when I find some time to take a closer look!