Hammer testing everything, always

We now run hammer_test on macOS, Linux with kqueue, epoll and libuv via GitHub Action on every push and PR
Hammer tests are now very stable on both macOS and Linux and can be run many times over in a loop for hours, collecting potential bugs
Fixed OpenSSL socket adoption bug found by hammer test
Fixed libuv resize bug found by hammer test
Hammer test now features a slim progress bar with minimal output
It is now possible to check the port of a listen socket if you specified 0 as port
It is now possible to put a timeout on a connect socket
Connect sockets now error in a new event; on_connect_error
It is now possible to abort a connect socket
Is is now possible to check if a socket is established or not (listen sockets and connect sockets are not established)
Sockets can be "defer-closed" next event loop iteration
Various build fixes on macOS such as Swift examples, GCD event loop

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