Add more details to login attempts regarding username / port / etc

[Gideon Bakx]

When logging an access attempt, in the current version there is a field called Details that contains some of the details, however in order to get better insight in additional details like which usernames / ports are mostly targeted, they could get stored in a new column called Custom1 (perhaps add Custom2 and Custom3) for future purposes.

Suggestion:
Custom1 : nvarchar(255)
Custom2: int32
Custom3: 3int64