* allow ExpireInSeconds < 0
Allow `ExpireInSeconds < 0` for use with `KVSetWithOptions`. While this has no practical use in reality, it's much easier to thoroughly unit tests the underlying functionality if we can match the semantics of CompareAndSet. Strictly speaking, this is a breaking change, but not relative to the advertised semantics. Anyway, it's also not entirely unreasonable to treat a negative `ExpireInSeconds` as having already expired vs. marking it as never expired.
* updated tests, to break apart
* honour expiry in CompareAndSet
* honour expiry in CompareAndDelete
* honour expiry in List
* fail unique constraint exception for SaveOrUpdate
A unique constraint error on a `SaveOrUpdate` should not be ignored: we did not save or update the requested value, as someone else managed to write the record first.
Note this is handled differently in `CompareAndSet`, where we correctly swallow the error and return `false` to indicate we did not successfully save the value.
* unexport DEFAULT_PLUGIN_KEY_FETCH_LIMIT
* s/InternalServerError/BadRequest/ for failed SaveOrUpdate
Co-authored-by: mattermod <mattermod@users.noreply.github.com>
* Consistent license message for all the go files
* Fixing the last set of unconsistencies with the license headers
* Addressing PR review comments
* Fixing busy.go and busy_test.go license header
