GEMS16 — Clarify time parameter descriptions

The "time" parameter in Table 8.1 indicates 9 places for seconds (decimal), however any contemporary UTC time needs 10 places for seconds (see examples from GEMS web site).

For the "utime" parameter in Table 8.1, clarify the description for:
ss - seconds (00-59), and
[.nnnnnnnnn] - nanoseconds (9 digit number).

Update time and utime examples

Update the "time" and "utime" examples in Table 8.1 of section 8.2.1.1 per the Revised Text.