code: function checkGauge(method, gauge) {
          if (!gauge) {
              throw new Error('SVOGauge.init: method ' + method +
                              'did not create element gauge.');
          }
          if ('function' !== typeof gauge.getValues) {
              throw new Error('SVOGauge.init: method ' + method +
                              ': gauge missing function getValues.');
          }
          if ('function' !== typeof gauge.enable) {
              throw new Error('SVOGauge.init: method ' + method +
                              ': gauge missing function enable.');
          }
          if ('function' !== typeof gauge.disable) {
              throw new Error('SVOGauge.init: method ' + method +
                              ': gauge missing function disable.');
          }
          if ('function' !== typeof gauge.append) {
              throw new Error('SVOGauge.init: method ' + method +
                              ': gauge missing function append.');
          }
      }
docs: ## Helper functions. 
  ### checkGauge
  
  Checks if a gauge is properly constructed, throws an error otherwise
  
  @param {string} method The name of the method creating it
  @param {object} gauge The object to check
  
  @see ModdGauge.init