Added test cases for DateTimeParser and DateParser in
DateTimeParserTest.
Added test cases for TimeParser to DateTimeParserTest.
Merge branch 'master' of https://github.com:443/cs2103aug2014-w11-1j/main.git
Added comments to date/time parsing classes.
Slight refactoring for DateParser, DateTimePair, and DateTimeSequence.
Changed access of ParsedDate.