Refactor batch actions in `CMSMain`/`HierarchyModelAdmin`

[GuySartorelli]

Batch actions at best only work for versioned records, but possibly only work for SiteTree specifically.

These should be updated to only show the actions that can be performed on the given model.

Related

• Batch actions form - Custom parameter fields enhancement #2744
• SPIKE Analyse how LeftAndMain and CMSMain are put together and how they could work better #2933

Notes

• There is currently no built-in equivalent to batch actions for GridField but there is https://github.com/silverstripe/silverstripe-gridfield-bulk-editing-tools
  • If it's not a lot of additional work, see if batch actions can be generalised and reused for gridfields.

Acceptance Criteria

• All batch actions that are for versioning actions work for all models with the Versioned extension applied
• Batch actions are only shown for models they can apply to
  • Note that since custom batch actions can be added, we'll need an API to allow developers to indicate what criteria must be met
• If there are no batch actions applicable for a model class, the option isn't displayed at all.