Patch for pgAdmin 4 docs

Hi All,

At this point I have not made any major changes to the way the TOC/indexes are set up.

There were a lot of inconsistencies in the .rst files (bad links, incomplete names, extra line spacing, etc.) Some caused Warnings when I generated the html, and some did not. In either case, as I updated the files to remove an inconsistency, the problems with expanded sidebar seemed to correct themselves.

As a rule, I don't like it when seemingly unrelated changes seem to fix a problem (I'd much rather know why something makes a difference), but it's working properly locally now (with a shorter, neat sidebar that only expands the current node index), and if I roll back the changes, there are still problems within the files that ultimately need correcting.

Thanks!

-- Susan