In preparation for using any 2FA solution, it will most likely need to modify sshd_config, so let's change the file in place instead of overwriting it completely.
Merge pull request #198 from jplock/jp-sshd-simplification

Modify sshd_config in place
Added Google Authenticator 2FA logins
Automatically generate the Google authenticator file for the default user
Clarified parameters are bit in a comment
Merge pull request #199 from jplock/jp-googleauth

Added Google Authenticator 2FA logins
Update README with 2-factor auth
The .google_authenticator file has to be generated by the user that is going to attempt to use it.  Also, -W doesn't seem to work (results an in INVALID_WINDOW error in /var/log/auth.log), so use -w 1 to allow for a single concurrent token
Merge pull request #203 from jplock/jp-fix-google-auth-generation

Fix Google Authenticator file generation