Flags break_, is_sending, is_receiving, is_pause are accessed from
both the send thread (send_process) and the read thread (received)
without synchronization. Plain bool reads/writes from multiple threads
is undefined behavior per C++ standard. Convert to std::atomic<bool>
with proper initializers.
in almost all methods removed timeouts in milliseconds, replaced to PISystemTime
PITimer rewrite, remove internal impl, now only thread implementation, API similar to PIThread
PITimer API no longer pass void*
PIPeer, PIConnection improved stability on reinit and exit
PISystemTime new methods
pisd now exit without hanging