What better thing to do during a long train ride than refactoring ;-)

more to come

I changed my mind about the more complex configuration options. We go with good default for now and don´t expose all the technical options to the users.
They can still override in the config file if it´s really really needed and they know what they are doing

Contacts: Ensure TYPE parameters on email aren't deleted on edit. They are still not shown in the UI.
Remove an obsolute file and did some cleanup.