Fixes instrumenting of cron to preserve environment variables.

[krobertson]

This changes the startup script to create a crontab with all of the
supported environment variables prepended to it to ensure they are
available when calling to arkmanager.

This fixes an issue where updating and restarting from cron would fail
to restart the server properly.

This change also includes a number of trailing whitespace trims, as well
as an update to the README where the Variables section had a typo for
the UPDATEONRESTART entry.

Fixes #13 and arkmanager/ark-server-tools#678

[changemenemo]

what's your start command of the container

[krobertson]

I just use the default one. Dockerfile has it call user.sh.

[krobertson]

I repushed the krobertson/ark:test image I posted on Docker Hub. If you were using it before now, you'll want to repull. I realized I hadn't re-pushed it after correcting the UPDATEONRESTART spelling. Having it wrong resulted in the crontab not loading at all because of a syntax error.

Also, worth noting the startup scripts do not have set -e where an error in the setup does not result in the container failing.

[TuRz4m]

Great work :) I saw your issue on Ark Server Tools this weekend but I wasn't available. If you're sure it works, I can merge it right now, but I don't have time to test it before the end of the week.

[changemenemo]

ow ow finally turzam show himself :p @krobertson Do you have look at your logs? you don't have different PID now?

[krobertson]

Was going to say wait for the next update to see, but looks like 253.71 came out and our server updated and restarted just fine.

[changemenemo]

and nothingin the logs?

[changemenemo]

it's our container itself who decide to go fetch the update right?