Changes
* PCBC-459: restore \Couchbase\Bucket::unlock() method, which has been
lost in refactoring
* PCBC-460: prefer managed strings to persistent when storing document
values.
* PCBC-461: deallocate intermediate results when using encoder compression
* PCBC-462: replace new lines in log entries with space
* PCBC-464: fix NumericRangeFacet with NULL boundary on PHP 5.4
* PCBC-463: fix incorrect reference counting on Search API. (might lead to
segfaults and leaks)
* PCBC-465: check encoded ViewQuery before sending to libcouchbase
* PCBC-467: intermediate values in Datastructures API might leak.
(e.g. result of internal "get" to find out size of the list)
* PCBC-469: implement SearchQuery->sort() function to support sorting FTS
results, which is accessible in Couchbase Server 4.6+
* PCBC-471: fixed issue, when the library always use credentials for the
first bucket in Authenticator.
* PCBC-441: add experimental support of Analytics query.
https://developer.couchbase.com/documentation/server/4.5/analytics/introduction.html