+Optional Merge Backends
+=======================
+Evolution Data Server 3.12.0+
+
+
+Optional Barcode Backends
+=========================
+GNU Barcode 0.98+ (http://www.gnu.org/software/barcode/barcode.html)
+QREncode 3.1.0+ (http://megaui.net/fukuchi/works/qrencode/index.en.html)
+IEC16022 0.2.4+ (http://datenfreihafen.org/projects/iec16022.html)
+LIBZINT 2.4.0+ (http://www.zint.org.uk)