Add logging to linkbcs.py

[mathomp4]

Recently @sinakhani was trying out the new linkbcs.py branch (#823) and concerning the linkbcs_config.yaml file:

From this file alone, it is difficult to see specific details like the KPAR, tile, and runoff files used, or where is the location of corrected precipitation if applied. The old linkbcs file used to display this info along with other things. Could you please point me to where this type of information is located in the new exp directory. My main concern is that without these details, the experiment might not be fully transparent or reproducible.

And this is valid. Talking with @tclune the first and most obvious step would be to add a logger to linkbcs.py. Then we could see everything it did?