Apply read-wants-write patch

Fix OpenSSL hammer_test failure

Add initial sni_tree test

Code & reason in close, recursion bugs in context create/free

Fix warning; us_socket_context_get_native_handle

BoringSSL: BIO_set_flags ORs flags

Fix a few Windows warnings

Hopefully fix SSL error queue bug

Implement us_internal_loop_unlink

Too much recursion in hammer test