SERVER-14623 fixed shell function ObjectId.fromDate for dates before 1978-07-04T21:24:15Z

ObjectId.fromDate is not correct for all dates

There is an under-run for dates less than 1978-07-04T21:24:15Z ('Math.pow(2,28) - 1' seconds)
Added extra test for upper date limit.

Closes #725

Signed-off-by: Benety Goh <benety@mongodb.com>