Docs update, fixes 83

[kd-ods]

I'll leave this as a draft PR in the first place. We still need to:

• Finalise and update the name of the plugin Plugin name #84
• Update the installation instructions after Add this plugin to the QGIS repository #89 is done

After merge:

• Update links to documentation from OFDS documentation site: https://standard.ofds.info/en/0.4-dev/guidance/use/#qgis

[duncandewhurst]

I added one to-do for after this PR is merged.

[kd-ods]

@Bjwebb - is schema-0-4 the branch that you're working on? If so I'll change the base branch on this docs PR accordingly, as we talked about last week.

[kd-ods]

@Bjwebb - I added the node deletion guidance to the docs. I've now changed this PR so that it'll merge into schema-0-4. I'll leave you to review and merge into your branch whenever you want.

[Bjwebb]

@kd-ods I've worked out a way to avoid the deletions issue: #88 (comment), I guess you may want to undo that docs edit.

[kd-ods]

@Bjwebb - I've undone the docs edit.

The tests are failing.... and not because of any readMe content ;-) Looks like an issue with tests around the new wayleave content in the 0.4 schema.

[Bjwebb]

Yes, those test failures are on the base branch, I will fix those before I merge.