code: function(name, language) {
  			name = (name || 'gregorian').toLowerCase();
  			language = language || '';
  			var cal = this._localCals[name + '-' + language];
  			if (!cal && this.calendars[name]) {
  				cal = new this.calendars[name](language);
  				this._localCals[name + '-' + language] = cal;
  			}
  			if (!cal) {
  				throw (this.local.invalidCalendar || this.regionalOptions[''].invalidCalendar).
  					replace(/\{0\}/, name);
  			}
  			return cal;
  		}
docs: Obtain a calendar implementation and localisation.
  @memberof Calendars
  @param [name='gregorian'] {string} The name of the calendar, e.g. 'gregorian', 'persian', 'islamic'.
  @param [language=''] {string} The language code to use for localisation (default is English).
  @return {Calendar} The calendar and localisation.
  @throws Error if calendar not found.