nmap.new_try() shouldn't be used in libraries. It results in Lua errors
being thrown that the script can't recover from without resorting to
pcall(). It has been replaced in proxy.lua with proper error handling
which did not require any changes to the scripts (http-open-proxy and
socks-open-proxy) that used it.
socket:connect(host.ip, port.number)
socket:connect(host.ip, port.number, port.protocol)
to this:
socket:connect(host, port)
connect can take host and port tables now, and the default protocol is
taken from the port table if possible.