checkstyle: unused import
add @Override annotations
The old picker in isLatin mode transmitted 1-12 not 0-11
In 24 hour format is 0-23 even if DatePicker.getHourRange()
and getHour javadoc is wrong (1-11!!!).
Fix javadoc. 1-11 makes no sense, and the old picker did
1-12 for am/pm time.