Allow for multiple hosts to be specified either via an array or a semicolon delimited list

This feature will configure the client library to automatically select another node from the cluster if the first node specified is down.

PCBC-77: Do not attempt to decompress uncompressed JSON.

This change allows for interoperability between the Java client library and the PHP client library, even though the flags may be slightly different between the two.

PCBC-75: Correctly free persistent structures.

Prior to this change, in some cases the client could encounter a segmentation fault while trying to use persistent connections.