[Fix] Allow passing Date()-objects to viewDate()

The datetimepicker was forcing passed in dates to be parsed with the local timeformat (see `actualFormat` in `initFormatting()`), even when passing actual moment.js-objects or Javascript Date-objects. This change allows using `Date()`-objects when setting `viewDate`.

Author: malthejorgensen

src/js/bootstrap-datetimepicker.js

@@ -142,6 +142,10 @@
 
                 if (d === undefined || d === null) {
                     returnMoment = moment(); //TODO should this use format? and locale?
+                } else if (moment.isDate(d) || moment.isMoment(d)) {
+                    // If the date that is passed in is already a Date() or moment() object,
+                    // pass it directly to moment.
+                    returnMoment = moment(d);
                 } else if (hasTimeZone()) { // There is a string to parse and a default time zone
                     // parse with the tz function which takes a default time zone if it is not in the format string
                     returnMoment = moment.tz(d, parseFormats, options.useStrict, options.timeZone);