#5 configure --with-user at runtime

[Alex]

Right now, as far as I can tell, the user allowed to run leafnode (default 'news') is set during compile. Is it possible, or could it be, to change that user afterwards? This would help us over at Homebrew (see https://github.com/Homebrew/homebrew/issues/45255#issuecomment-150898912) since we require that builds be sudo-free. We can set --with-user during the build, but we won't be able to provide our own compiled binaries and those will have user set to 'brew' .