code: function _find(model, _id, query, Log) {
    let request = { params: { _id: _id }, query: query }
    return _findHandler(model, _id, request, Log)
  }
docs: Find function exposed as a mongoose wrapper.
  @param model: A mongoose model.
  @param _id: The document id.
  @param query: rest-hapi query parameters to be converted to a mongoose query.
  @param Log: A logging object.
  @returns {object} A promise for the resulting model document.
  @private