Add parameter to copy custom init.d scripts.

[sebastianludwig]

As discussed in #151 I added a parameter to copy custom init.d scripts to Jenkins.

[sebastianludwig]

@geerlingguy Not "All checks have failed", one test got stuck installing Java. The added test succeeded. Can you trigger Travis again?

[sebastianludwig]

Never mind, I forgot to update the README. This time all checks passed 🎉

[sebastianludwig]

@geerlingguy is anything missing I can do?

[sebastianludwig]

@geerlingguy sorry that it took so long but I finally got around to add a real script to the test case. Anything else you'd like to have changed?

[jgerry]

I tried this PR today as it's something I need - works great! Merge away. I also added another option like this to manually install .hpi files for private plugins. My job requires our private pre-configured Okta plugin which needed this.

[nickbroon]

This is definitely very useful, and I'd love to see it merged.
It's specifically for the example case of starting jenkins in quiet mode that I'd like to use it.
https://wiki.jenkins.io/display/JENKINS/Post-initialization+script documents this.

[nickbroon]

@sebastianludwig can all changes requested (to add a test case) now be marked resolved?
https://help.github.com/en/articles/about-pull-request-reviews#resolving-conversations

@geerlingguy are you happy to now merge this PR?

[stale]

This pull request has been marked 'stale' due to lack of recent activity. If there is no further activity, the PR will be closed in another 30 days. Thank you for your contribution!

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[stale]

This pull request has been closed due to inactivity. If you feel this is in error, please reopen the pull request or file a new PR with the relevant details.