#55 Extended notification mail system

[Albrecht Günther]

This Feature applies to a version beyond 6.0:
The notification tab will be enhanced with the following properties:
- a subject line (prefilled with the title of the record)
- a body textarea (prefilled with the remark of the record)
- a multiple select box with user/recipients (user with read acces are preselected)
- a text field to add more recipient addresses manually