alternator: table creation time is in seconds
alternator: table creation time is in seconds

The "Timestamp" type returned for CreationDateTime can be one of several
things but if it is a number, it is supposed to be the time in *seconds*
since the epoch - not in milliseconds. Returning milliseconds as we
wrongly did causes boto3 (AWS's Python driver) to throw a parse exception
on this response.

Signed-off-by: Nadav Har'El <625169824b719df98706d88646d0aae6f368ae4d@scylladb.com>

scylladb/scylla,scylladb/scylla,avikivity/scylla,avikivity/scylla,scylladb/scylla,scylladb/scylla,avikivity/scylla