This change allows documentation page paths to be redirected to other

pages. We follow what we do for our Review Board codebase docs, where we:

- Add a redirects.json file that contains the redirect info

- Point to that file in collect_file_patterns in our conf.py

- Rely on the beanbag_docutils.sphinx.ext.collect_files extension to

  collect the redirect info.
In 2024, HCL rebranded VersionVault to HCL DevOps Code ClearCase.

Power Pack 6 renames the VersionVault / ClearCase SCM tool to

ClearCase. This change updates the RBTools documentation

accordingly. We keep all of the old reference labels alongside the new

ones, to make sure any existing documentation that uses the old labels

still works. 
We don't need to add the new SCM tool name (ClearCase)

to the server_tool_names list on the Clear Case client, because the

server_tool_names list will match against the SCMTool.lookup_name

instead of SCMTool.name on Review Board 6.0.3+, which points to the

old VersionVault / ClearCase name in Power Pack 6. This means that

older versions of RBTools will be compatible with Power Pack 6, as long

as they are using Review Board 6.0.3 (which is already a requirement

for using the SCM tool and hosting service features in Power Pack 6).

RBTools 5.0.1+ matches SCM tools using server tool IDs instead of

relying on tool names anyways, so we don't have to worry about renaming

and compatibility moving forward either.

Built the docs, served them on rbwebsite and viewed them. Made

  sure redirects work.