v3.3.5

Add support for send and receive timeouts on requests and available checks:

• Move client timeout (for request/response) to the ZMQ layer since ZMQ 3 supports timeout on the socket layer directly. It works better than a poller/polling item and makes the timeout intervals configurable (via the PB_ZMQ_CLIENT_SND_TIMEOUT and PB_ZMQ_CLIENT_RCV_TIMEOUT environment variables, both default to 300 seconds).
• Set send and receive timeouts to fix an issue where ZMQ clients hang when sending available checks to servers that have are in the process of shutting down by (configurable via the PB_ZMQ_CLIENT_CHECK_AVAILABLE_SND_TIMEOUT and PB_ZMQ_CLIENT_CHECK_AVAILABLE_RCV_TIMEOUT environment variables, both default to 200 milliseconds).

Adding these timeouts made a significant change in time to recover after a process failure or process blockage