configurer: handle None for timestamps
configurer: handle None for timestamps

Senseg/robotframework,userzimmermann/robotframework-python3,Senseg/robotframework,userzimmermann/robotframework-python3,Senseg/robotframework,Senseg/robotframework,userzimmermann/robotframework-python3,userzimmermann/robotframework-python3,Senseg/robotframework,userzimmermann/robotframework-python3