[Time] Add missing setFullYear, getSeconds, setSeconds
[Time] Fix secondsFromUTC() and add getTime()
[Time] Fix getDay misunderstanding

getDay() returns the day of the week (0 - 6)
getDate() returns the day of the month (1 - 31)
[Time] Refactor TimeDuration

Some tests needed to access its variables 'length' and 'unit'
[Time] Fix TZDate constructor

Some of the arguments are optional
[Time] equalsTo, earlierThan and laterThan now are throwing exceptions
Merge pull request #141 from ricardotk/wip

Time API fixes