BUG: NewWithTime uint wrap around causes xid to return wrong time

[N-o-Z]

When using NewWithTime, the time object Unix method returns a uint64 which is then cast into a uint32.
Using a future time which exceeds uint32, the xid object returns the wrong timestamp.

Code example:

	nt := time.Unix(4294967296, 0).UTC()
	fmt.Println("time wrap around: ", nt)
	idd := xid.NewWithTime(nt)
	fmt.Println("xid time vs actual: ", idd.Time().Unix(), nt.Unix())

output:

time wrap around:  2106-02-07 06:28:16 +0000 UTC
xid time vs actual:  0 4294967296
0 1970-01-01 00:00:00 +0000 UTC

I feel the need to emphasize that this is not a "future" problem. This is a current issue that impacts code today.
xid needs to respect time object values whether past, present and future and is expected to return the correct object when xid.Time() is called