Add nginx Rockon Documentation #488

[Hooverdan96]

Fixes #488.

This pull request's proposal

Add a write-up for the nginx Rockon
This PR is based on the work that Rockstor community forum user Stevek compiled.

Changes implemented:
Add nginx Rockon documentation

• nginx document initial release (using Stevek's version, updating formatting, some minor changes)
• link into Rockon overview page (section of Rockons with write-ups)
• add to Authors file

Checklist

• With the proposed changes no Sphinx errors or warnings are generated.
• I have added my name to the AUTHORS file, if required (descending alphabetical order) - in this case Stevek (or kaufstev on github).

[Hooverdan96]

There are a couple of link checks that are failing not related to this addition. Will check it out eventually and attempt to fix them. Also a few permanent relocations of targets seems to have occurred recently.

[phillxnet]

Thanks to Steve Kaufman on our forum for main authoring and instigating this Rock-on write-up. And to @Hooverdan96 for seeing this work through to submission here on GitHub.

This is a super write-up with some really nice clarification points: particularly pertaining to the 'overlap' that can be hard to grasp regarding the docker instance and the base OS (openSUSE) instance of Nginx. Nice. As such it should server as a good write-up for those in need of a local development instance of Nginx.

I have some modifications I'd like to see regarding repetition (intra, and inter doc section), and some company links I would rather not have in-place. Plus a country reference that is inappropriate given Nginx's open-source world wide contributor base etc. Plus a few trivial capitalisation etc. But overall this is good to go and my modifications can wait and undergo a review process of their own. Given @Hooverdan96 (core-contributor) has already prepared this, lets get this in and published so we can get more eyes on what folks might want to see improvemnets wise.

Thanks again to Steve & @Hooverdan96 for all the work in getting this to this stage. And my apologies for not being able to contribute to that effort. But I do plan to present a PR in time with my suggested changes here: mainly regarding a simplification re repetition of what is already written-up re Rock-ons really: but essentially just stylistic.

I'll get this merged and published shortly so others can more easily contribute as they see fit.

[phillxnet]

My main outstanding issue here really is the confusing inclusion of systemd references to the OS Nginx instance via systemd. This entire section can be removed as we are only wanting to give instructions on the Rock-on itself. But I do see the point. And again we can have this discussion via any number of follow-up PR. But I'm keep to get Steve's & @Hooverdan96 effort published as it is easily at the same level as any other section of our docs that could be picked out :). I think we also should avoid first person references such as " I will explain their use below.". Our project is always a team effort: but again this is a trivial modification that is not worth delaying further the publishing of what looks like a useful contribution for perspective web developers who need a local instance of Nginx to prove their proposed deployments/configurations.

N.B. I also had a functional issue with the f5 link (maintenance indicated). But I'd like to remove that link in time anyway.

[phillxnet]

We have some rockstor-core changes pending re Rock-ons summary/info screens that will also impact an image o two here (and mixed png/jpg). But again no show-stoppers: just cleaner presentation to come, and some normalisation we need to establish across our docs anyway.

[phillxnet]

PR product PRODUCTION published.