add a way to ensure a fiber is woken when a multi_signal is raised
add a way to ensure a fiber is woken when a multi_signal is raised

marioskogias/libfiber,marioskogias/libfiber,brianwatling/libfiber,marioskogias/libfiber,brianwatling/libfiber,brianwatling/libfiber,marioskogias/libfiber,brianwatling/libfiber