SUSYTools: import from rel21.2

This MR ports SUSYTools from rel21.2. As this is an initial import, it would be great if we can postpone code review, further feature fixes, and further cleanup etc. to future MRs. Development will ease massively if we get this first version into master. If we need a place to discuss anything related after this MR, feel free to use ATLSUSYBGF-581.

A couple notes:

• We shouldn't be dependent on any missing tools at the moment, I expect this thing to run properly for all objects.
• Currently one data and one mc ctest are configured. They have updated references and run mostly properly, but suffer from a random result change with the muon resolution bias systematic, for which we'll open an MCP Jira (ATLASMCP-98).
• One ART test is available, but I have no idea if it's properly configured to run in the system.
• A temporary slice setup is configured inside SUSYTools to allow running without certain objects while we develop the release 22 version. This isn't fully tested (ie. things might crash if you disable too many or the wrong objects), but it is very helpful for debugging, and the intention is to either improve it or to remove it once we have a more stable release 22 SUSYTools.
• I've left a lot of commits in the MR, going back to the start of the development in October. There's been many rebases inside this branch too, but so far still behaves fine for me within the gitlab system. I have no idea if you prefer to squash it all or keep the history, a lot of the disable/enable bits are ancient history now, but some of the syntax / header changes might be easier to check back on if we have the specific commits.

Tagging: @janders, @cmerlass, @lheinric, @alister, @zmarshal

Cheers,
Sara