Permissions: minor refactors

[ErisDS]

This PR includes cleanup, refactors & renaming to check off 3 items from #9043. The aim is to make it easier to understand the code. Can use this PR description as squashed commit message 🐿

refs #9043

Cleanups / refactors to make the code more manageable:

• Move remaining code out of index.js
  • Only "init" function is left. Actions map cache and init function is based heavily on the settings cache module
• refactor the odd way of exporting
  • This was cleaned up naturally by moving the actionsMap object out
• rename "effective" -> "providers"
  • "Providers" provide permissions for different things that can have permissions (users, apps, in future clients).