Updating the DataTime printout

[srcarter3]

It would be helpful if the default print string for a dataTime object also included the forecast hour if that's available.
It does seem like the current print string logic tries to accomplish this, but it doesn't seem to be working in practice.

To replicate, use any of the model notebooks and print out a DataTime object that's used to request the data, you'll see it doesn't show the Forecast Hour, which can be confusing because two different DataTime objects can print out the same string.