Log Message:
py-vobject: updated to 0.9.6

0.9.6:
Correctly order calendar properties before calendar components
Correctly serialize timestamp values (i.e. REV)
Pass correct formatting string to logger
RRULE: Fix floating UNTIL with dateutil > 2.6.1
Encode params if necessary in serialization
Ignore escaped semi-colons in UNTIL value
RRULE: Fix VTODO without DTSTART
Fixed regexp for VCF Version 2.1
repr changed for datetime.timedelta in python 3.7