Changes:
* PCBC-331: CouchbaseBucketManager now has a flush operation to clear a bucket.
* Orphan: Minor fix to view management return values.
* Orphan: ViewQuery::group_level now can be chained as expected.
* PCBC-334: PHP 5.4 transcoder compatibility issues have been fixed.
* PHP 5.3 support has been deprecated and PHP 5.6 is now fully supported.
* Corrected various memory leaks and segfaults.