java.util.Date support in Map to JsonObject converter

javax.json.Json #createObjectBuilder(Map map) methods throws error :
` Type class java.util.Date is not supported.`, If type of value is `java.util.Date` in input map.

Start at the createObjectBuilder(Map) entry point and trace how map values are converted, then inspect the existing tests for supported value types. The issue does not specify the intended JSON representation for java.util.Date, so confirm that behavior before making a change. Done should include a defined Date conversion and coverage for a Date-valued map entry.

Written by the indexing model from the issue text.