nghttpx: Stop watchers in ConnectionHandler dtor
nghttpx: Stop watchers in ConnectionHandler dtor

wzyboy/nghttp2,thinred/nghttp2,thinred/nghttp2,icing/nghttp2,serioussam/nghttp2,thinred/nghttp2,thinred/nghttp2,icing/nghttp2,serioussam/nghttp2,serioussam/nghttp2,icing/nghttp2,thinred/nghttp2,serioussam/nghttp2,wzyboy/nghttp2,wzyboy/nghttp2,thinred/nghttp2,serioussam/nghttp2,thinred/nghttp2,wzyboy/nghttp2,icing/nghttp2,wzyboy/nghttp2,serioussam/nghttp2,icing/nghttp2,icing/nghttp2,serioussam/nghttp2,icing/nghttp2,wzyboy/nghttp2,wzyboy/nghttp2