R1:3f5a55fa6e5a

Let users review their own account activity logs

Summary:
Ref T4398. This adds a settings panel for account activity so users can review activity on their own account. Some goals are:

- Make it easier for us to develop and support auth and credential information, see T4398. This is the primary driver.
- Make it easier for users to understand and review auth and credential information (see T4842 for an example -- this isn't there yet, but builds toward it).
- Improve user confidence in security by…