Comment 4 for bug 964365

In bried:

- it doesn't find sunset/sunrise timestamp in http://www.earthtools.org/timezone-1.1/41.3887868891/2.15898513794
- __sunrise_t and __sunset_t in /usr/bin/indicator-weather remain None
- in helpers.py, format_time fails because t is None

Solution, change:

@staticmethod
def format_time(t):
    """ do the format """
    return t.strftime(TimeFormatter.format)

To:

@staticmethod
def format_time(t):
    """ do the format """
    if not t:
        return "Unknown"
    return t.strftime(TimeFormatter.format)