1202 index file cleanup

[ipopescu]

What does this PR fix/introduce?

• Removes unnecessary Introduction/Overview/Index pages in sidebar
• Adds missing index files in the operators section, where they seemed necessary
• Clean up of the operators section since the index files were introduced. As a result of this PR, the operators section doesn't need to be updated in cards TOC / Overview / Introduction (CAS-65) #1200 and Review order in the left sidebar (CAS-62) #1199.

Open question for @ACStoneCL: sometimes articles are missing in a sidebar, to keep titles shorter, but I kept them in this PR. Examples: Archive and Restore a DB vs. Archive and Restore DB, Move a Node vs. Move Node, Join a Network vs. Join Network. What do you think?

I've discovered issue #1216 while working on this PR.

Closes #1202

Checklist

• Docs are successfully building - yarn install && yarn run build.
• For new internal links I used relative file paths (with .md extension) - e.g. ../../faq/faq-general.md - instead of introducing absolute file path, or relative/absolute URL.
• All external links have been verified with yarn run check:externals.
• My changes follow the Casper docs style guidelines.

Reviewers

@ACStoneCL @andrzej-casper

FYI @Adrian-Wrona

[ACStone-MTS]

Content LGTM - as far as the titles in the sidebar, I don't have a strong opinion beyond making sure that they are easily readable.

[ipopescu]

Thanks @ACStoneCL!

[ghost]

Now it's much easier to navigate sidebar and breadcrumbs are working 😁

---

I found one place where collapsible category is not merged with index (thus breadcrumb is broken):

I suggest moving subpage Introduction directly to Why Build on Casper, and moving out Ecosystem Open-Source Software.

[ghost]

Top level sections can be shown with #1219.

[ipopescu]

@andrzej-casper I am addressing your request in this branch: 1200_navigation_resources. I started doing the change you requested right after our call, but the PR got too big. Please approve this one, and then I will raise another PR for the 1200_navigation_resources branch. I am trying to break down the work in manageable PRs, but there is still some inter-connectedness.

[ghost]

@ipopescu Let's merge it then!