Allows you to bulk edit the Addressbook, for example with an external tool.
Will overwrite all current entries, so be careful what you do here.
The format needs to be exact (you can use the Test-button to check your input):
name1 category1,category2 name2 category1 name3 name4 category2,category1,category3
Entries here are initially always ordered alphabetically by name, strictly for convenience, the order does otherwise not matter.