Implement Permissions Improvements

[rdig]

Implement improvements pointed out in the review of #60

And the conclusions that were drawn in the subsequent call: https://www.notion.so/colony/Permissions-Events-26-04-23-ea5f7fe0b34c42289056afd95fcbc1f5

The most relevant here being refactoring the logic behind role events being handled one at a time vs. (currently) on a tx basis (all events in the transaction)

Note: This was extracted into this issue in the interest of time, as to be able to launch faster