0.5.3 Release: Global Permission Wipe

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The permission system is on the verge of being replaced and a strategy needs to be picked for migrating to the new permission system.

This is mostly to see what people would prefer to happen, some notes:

• Migrating all permissions comes with two issues:
  1. Old defaults were not well chosen and are going to be annoying to remove.
  2. This will cause a significant delay on the release since the two systems are entirely incompatible and mappings need to be constructed to accommodate for it.
• Migrating role permissions is tricky hence why the send message migration is split into two.
• The first option will mean we are ready for release immediately.
• The second option is probably the best compromise since it allows everyone to have a fresh start but does not cause the platform to devolve into chaos. The migration should also be fairly straightforward.

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Implemented default SendMessage migration in dd3c1283a0398a4ee575a0a4c6e81c1f4aebcb46.