epee::copyable_atomic was only be used by one struct, cryptonote_connection_context.
This should probably eventually factored out of that class, so I left the following comment:
This class was originally from the EPEE module. It is identical in function to std::atomic<uint32_t> except
that it has copy-construction and copy-assignment defined, which means that earliers devs didn't have to write
custom copy-contructors and copy-assingment operators for the outer class, cryptonote_connection_context.
cryptonote_connection_context should probably be refactored because it is both trying to be POD-like while
also (very loosely) controlling access to its atomic members.
bd0a511995