code: function propertyValueExtract(context, name, propName, options) {
    if (context[name] === undefined || context[name] === null) {
      return options.inverse(context);
    }
    this[propName] = context[name];
    /* eslint-disable no-param-reassign */
    context[propName] = context[name];
    /* eslint-enable no-param-reassign */
    return options.fn(context);
  }
docs: Extract the name of a property with a handlebars-unfriendly
  name, such as hyphenated names. Sets the property called name
  into context.propName if it exists and excutes the first block
  with context value.
  
  Executes inverse block otherwise.
  @param {object}      context       - Object to look in.
  @param {string}      name          - Property name
  @param {string}      propName      - New target property name.
  @param {object}      options       - Handlebars options.
  @return {string}                   - Handlebars result