revert ZOnedDateTime to joda.DateTime
ref #6860: use timezone offset 0 and change joda DateTime to ZonedDateTime, until in lib DateTime is still joda a converter is used
cleanup
remove pattern string from DateElement when no data are available
ref #6658: add calendar widget to dateElement
fix #6658: add mediaCreated date field
ref #6190 removing svn property place holder in first line of code - java files