INCR/DECR API breakage

Steps to reproduce

1. Create a counter

   cbc-incr -Ucouchbase://localhost/default id --initial 0 --delta 1 -e 600 -u Administrator -P password

1. Note the expiry in the UI
2. Update the counter

   cbc-incr -Ucouchbase://localhost/default id --initial 5 --delta 1 -e 600 -u Administrator -P password

3. Note the expiry in the UI

Problem

The expiry should not have changed on update. In previous versions of Couchbase Server the TTL for incur/decur operations is only set when the counter was created and not when it was updated.

Expectation
For Spock to behaviour like previous versions of Couchbase Server