Accounts Sync with Multiple Databases

Done:

• Added functionality to sync user account details to multiple databases
• Added config to define which databases to sync to

Notes:

• Implements in https://git.customd.com/dandi/pulse/merge_requests/393

Test:

1. Log in and go to the account admin area (https://www.zon.dev/admin/accounts/users)
2. Edit your account. Make some changes and confirm it works as you'd expect.
3. Jump into your database and duplicate the entire database with a new name.
4. Update your database config config/dev-sam/database.php, copy the existing and paste it as a second database config. Give it a new key and confirm the database name is updated.
5. Copy the config/accounts.php file and paste it into your config directory - config/dev-sam/accounts.php.
6. Edit the config/dev-sam/accounts.php file and add the new database config key to the extra_databases config parameter.
7. Repeat steps 1 to 2
8. Check the bitauth_userdata in both databases and config the changes have been saved into both.