proxy.sh 取消kill的错误输出，不美观

原型
kill -9 `ps aux | grep 'python2.7 proxy.py' | grep -v grep | awk '{print $2}'` || true
修改
kill -9 `ps aux | grep 'python2.7 proxy.py' | grep -v grep | awk '{print $2}'` >/dev/null 2>&1 || true