Update bootstrap.v3.datetimepicker.d.ts

Added four missing properties. See http://eonasdan.github.io/bootstrap-datetimepicker/Options/#showtodaybutton
There's still quite a few missing but I'm running short on time.

bootstrap.v3.datetimepicker/bootstrap.v3.datetimepicker.d.ts

@@ -48,6 +48,10 @@ declare module BootstrapV3DatetimePicker {
         direction?: string;
         sideBySide?: boolean;
         daysOfWeekDisabled?: Array<any>;
+        calendarWeeks?: boolean;
+        format?: string | boolean;
+        locale?: string;
+        showTodayButton?: boolean;
     }
 
     interface Datetimepicker {
@@ -97,4 +101,4 @@ interface JQuery {
     on(events: 'dp.error', handler: (eventObject: BootstrapV3DatetimePicker.DatetimepickerEventObject) => any): JQuery;
 
     data(key: 'DateTimePicker'): BootstrapV3DatetimePicker.Datetimepicker;
-}
+}