Changes to logging and initialization of the CLM Lake Model.

1. Use ice thickness hice(i) to find the level in the lake where ice is
   zero.
2. Do not allow lake temperature to be below freezing point if there is
   no ice.
3. If there is no snow or ice, do not allow surface lake temperature to
   be below freezing point.
   These changes fixed the problem with large errors in the energy budget
   at the beginning of the cold-start run with lakes.
4. Added flag to turn on debug print statements in the CLM lake model.