update_burn_rates throws an exception under certain circumstances

[cugarteblair]

need to add a function to clamp the ddt times calculated to reasonable values

[cugarteblair]

will add this function to version_four: def clamp_time(hours): days = 0 if hours < 0: hours = 0 else: if hours > 24: days = int(hours/24) if days < 365*5: hours = hours - days*24 else: days = 365*5 hours = 0 return days,hours

[cugarteblair]

This is fixed in v3.2.12