Changes
* PCBC-473: fix incorrect bucket reference copy in subdocument
mutation/lookup builders, which might lead to segfault.
* PCBC-474: fix segfault when using ViewQuery::keys()
* PCBC-476: do not call destructors on unintialized ZVALs. Fixes possible
segfaults with view queries on PHP 5.x.
* PCBC-477: lookup JsonSerializable interface in run time, instead of compile time
using php_json_serializable_ce symbol. This fixes support on some 5.4-5.5 builds.
* PCBC-479: do not allow to create objects in invalid state. For example Cluster
might return an instance, and only show PHP warning on invalid arguments.
* PCBC-481: Bucket->counter() without specifying delta value results in
null pointer dereference.
* PCBC-482: mapSize/setExists/setRemove methods of Bucket did not check if 'get'
sub-request had thrown exception. This cause segfault, if operation executed on
keys which do not exist.
* PCBC-453: verify that ClusterManager supports ephemeral buckets
* PCBC-451: add RBAC support in \Couchbase\PasswordAuthenticator class (Couchbase
Server 5.x feature).
* PCBC-440: add experimental support of extended attributes for subdocument operations.