Updated tool tips and removed default data

[Klaven]

• Added a database migration that removed default data from the database
• Added smart documentation on each LDAP field in place of the default data.

[r0ckarong]

@Klaven Please review the comments in the trello card regarding the descriptions: https://trello.com/c/Ipsm0Da9/940-3-external-auth-ldap-documentation