SHOW CREATE SEQUENCE to output restart value

When a user is restoring from a mysqldump, or looking at a galera node previously ssted from a mysqldump sst, we really don't want them panicing that they are missing data that is derived from sequences.

anel's current work has placed the `CREATE SEQUENCES` at the end of the mysqldump, so regardless if its dumped with `--single-transaction` or not, the `show create sequence` at the time its executated will contain a usable sequnce number.

Rather than the original plan of extending `create sequence`, `show create sequence` can return a `setval(seq, nextnum)` as follows:

| s     | CREATE SEQUENCE `s` start with 100 minvalue 1 maxvalue 9223372036854775806 increment by 10 cache 1000 nocycle ENGINE=InnoDB |

| s     | SELECT SETVAL(`s`, 1024)                                                                                                  |