Revert "Store node details in the JSON datafile"

This reverts commit c2eaf8718a53349044e2210481a462a56f6ad817.
There seems to be a unit mismatch between nova and what is stored in the
JSON, and since it landed while CI is down, we can not be certain it is
a good patch, so revert it wholesale.

Change-Id: I9918dc06d9366841775ba3ce0efe9eace95cba3b