Previously, terminating a running server from the terminal would
sometimes print a benign warning message if the server was currently
handling an incoming packet. This happened because CNServer::step()
would continue handling the packet after CNServer::kill() released the
activeCrit mutex. Now it first re-checks if active has been set to false
in the mean time after acquiring the mutex.
This change subtly broke the poll() loop when a connection was removed,
because erasing an entry from fds would invalidate the iterator that
was still being used.
This reverts commit ec67cc6527.
CNProtocol, CNShared, CNStructs and Defines are now in core/.
CNLoginServer, CNShardServer and Monitor are now in servers/.
core/Core.hpp wraps all the core headers except for CNShared.hpp.
Defines.cpp has been renamed to Packets.cpp, and so has its
corresponding namespace, but not the header file. This is in preparation
for upcoming changes.