code: def add_JSscript(self, js_script, js_loc):
          
          if js_loc == 'head':
              self.jscript_head_flag = True
              if self.jscript_head:
                  self.jscript_head = self.jscript_head + '\n' +  js_script
              else:
                  self.jscript_head = js_script
          elif js_loc == 'end':
              self.jscript_end_flag = True
              if self.jscript_end:
                  self.jscript_end = self.jscript_end + '\n' +  js_script
              else:
                  self.jscript_end = js_script
          else:
              raise OptionTypeError("Not An Accepted script location: %s, either 'head' or 'end'" 
                                  % js_loc)
docs: add (highcharts) javascript in the beginning or at the end of script
          use only if necessary