Allow Late attributes > 24 hours

[sfinkens]

Currently the Late attribute is limited to 24 hours. It would be nice if it was unlimited.

>>> import ecflow
>>> ecflow.Late(complete="+48:00")
Traceback (most recent call last):
  File "myfile.py", line 2, in <module>
    ecflow.Late(complete="+48:00")
RuntimeError: TimeSeries::testTime: time hour(48) must be in range 0-23

I know I can split my workflow into smaller tasks, but I've come across a couple edge cases (database access, intermittent network problems) where this could be useful.