mime_db: Sniff rule must be on one line.

mime_db: OpenDocument file types

* Adds the OpenDocument file types to the mime database
includes regular files and templates.

* Adds icons to mime_db and artwork/icons

Change-Id: I55c7f79f53e09d5976e41c4d5a5292fc6be906d0
Reviewed-on: https://review.haiku-os.org/c/900
Reviewed-by: Stephan Aßmus <superstippi@gmx.de>