Changed Private keys to have content within pillar rather than the salt
file repository.

Changes sudoers entry to get values from pillar rather than assuming
all sudo users want root.

Ran into an error with Salt version 0.17.1:
Rendering SLS users failed, render error: Undefined jinja variable; line 32

After finding https://github.com/saltstack/salt/issues/8245, and working on
line 32, I surmised that line 28 might be the actual cause of the issue.

I just added a quick check to see if uid exists in user, just as the user uid
line does.

add support for sudouser being False.
change to adding sudoers config to /etc/sudoers.d/<user>
adding the removal of /etc/sudoers.d/<user> on user removal or switching to sudouser being removed or set to false

Pulling 'shell' from pillar globally makes no sense, probably a mistake; pulling it from user instead.

group requisites were wrong. They required {{ group }}_group, while {{ group }} was the actually added group.