Allow passing options to Highcharts.setOptions()

[soroush-op]

This is related to https://github.com/daemth/easychart/issues/69 and How to pass options to Highcharts.setOptions() issue for Drupal Easychart module.

Here, a new setGlobalOptions() method is added to Easychart which allows setting options such as lang.thousandsSep option in Highcharts (The default thousandsSep is space character.) Currently, the only way to set such options is to call Highcharts.setOptions() directly and not through Easychart:

Highcharts.setOptions({
  lang: {
    thousandsSep: ','
   }
  });

Thanks!