Downgrade some template encapsulation logs to warnings

* These really are warnings since the template encapsulation algo
  now handles fostering properly and are no longer hard errors.

  This downgrading also makes it easier to sift through the log
  noise in logstash. We want error events to really be genuine
  errors so we can quickly search for them.

Change-Id: I2973af713cdb0e2994d150836ee19a1d78c986ca