logilab-common #6060938 datetime2ticks doesn't work anymore with date [validation pending]

prior to c74bf0d253b8, one could give a python date object to datetime2tick, but this now causes a traceback:

AttributeError: 'datetime.date' object has no attribute 'microsecond'
prioritynormal
typebug
done in1.2.1
load left0.000
closed by#63de39be70f2 Fix regression with datetime2ticks vs date object as argument
patchFix regression with datetime2ticks vs date object as argument [applied]