bugfix DateTime

## Wrong TimeSpan Parameter
`new TimeSpan(time)`
From msdn:
>TimeSpan(long ticks) :
>A single tick represents one hundred nanoseconds or one ten-millionth of a second. There are 10,000 ticks in a millisecond.

## Missing Check DateTime Kind
`encodeUTCDateTime(MemoryStream ms, DateTime dt)`
if dt's type is not local time, don't convert it to local time.