Update ug

[fossell]

Mods mainly to overview section of UG. More to come but this PR gets the first chunk of changes in. To view these mods on RTD, see my branch here. This is part of #84.

• [ ] Do these changes modify the system output in any way? [No]
  If yes, please describe:
  

Pull Request Testing

• [ ] Describe testing already performed for these changes:
  Mods with viewed on RTD branch

• [ ] Recommend testing for the reviewer(s) to perform, including the location of input datasets, and any additional instructions:
  Ensure only doc changes are being made. Review sections and provide suggestions for improvements as you see fit. Also ok to merge these in and refine later. Schematics not final. This is not a completed documentation update. Just getting this first chunk into the develop branch.

• [ ] Do these changes include sufficient documentation updates, ensuring that no errors or warnings exist in the build of the documentation? [Yes or No]

• [ ] Do these changes include sufficient testing updates? [Yes or No]

• [ ] Will this PR result in changes to the test suite? [Yes or No]
  If yes, describe the new output and/or changes to the existing output:
  

• [ ] Please complete this pull request review by [Fill in date].
  November 11, 2022

Pull Request Checklist

• [x] Review the source issue metadata (labels, project, and milestone).
• [x] Complete the PR definition above.
• [ ] Ensure the PR title matches the feature or bugfix branch name.
• [ ] Define the PR metadata, as permissions allow. Select: Reviewer(s) Select: Project Select: Milestone as the version that will include these changes Select: Development to link to the original development issue.
• [ ] After the PR is approved, merge your changes. If permissions do not allow this, request that the reviewer do the merge.
• [ ] Close the linked issue and delete your feature or bugfix branch from GitHub.

[fossell]

@JohnHalleyGotway - Do you think you could help me understand the tests and failures here? I poked around a little bit but sure exactly what's going on. I'll try to spend more time Monday on it, but might need some help anyway.

[fossell]

@JohnHalleyGotway - Oh, I just remembered the artifacts and am able to see the documentation error: /home/runner/work/wrfcloud/wrfcloud/docs/Users_Guide/overview.rst:5: WARNING: Duplicate explicit target name: "comet". But not sure how to solve it.

[fossell]

These mods have ben moved to a new PR #98.