Add ipset package

Author: alanpeng

.travis.yml

@@ -24,7 +24,7 @@ jobs:
       - >
         docker run -t --rm -v ${PWD}/debs:/root/debs -v ${PWD}/apt-download-without-version.sh:/root/apt-download-without-version.sh ubuntu:16.04 bash -c
         "apt-get update &&
-         /root/apt-download-without-version.sh 'python python-docker python-chardet python-requests docker-compose chrony jq ipvsadm graphviz nfs-common gnupg gnupg2' &&
+         /root/apt-download-without-version.sh 'python python-docker python-chardet python-requests docker-compose chrony jq ipvsadm graphviz nfs-common gnupg gnupg2 ipset' &&
          apt-get update && apt-get install -y apt-transport-https curl software-properties-common apt-utils &&
          mkdir /root/debs/ubuntu16 &&
          mv /tmp/debs/*.deb /root/debs/ubuntu16"
@@ -38,7 +38,7 @@ jobs:
       - >
         docker run -t --rm -v ${PWD}/debs:/root/debs -v ${PWD}/apt-download-without-version.sh:/root/apt-download-without-version.sh ubuntu:18.04 bash -c
         "apt-get update &&
-         /root/apt-download-without-version.sh 'python python-docker python-chardet python-requests docker-compose chrony jq ipvsadm graphviz nfs-common gnupg gnupg2' &&
+         /root/apt-download-without-version.sh 'python python-docker python-chardet python-requests docker-compose chrony jq ipvsadm graphviz nfs-common gnupg gnupg2 ipset' &&
          apt-get update && apt-get install -y apt-transport-https curl software-properties-common apt-utils &&
          mkdir /root/debs/ubuntu18 &&
          mv /tmp/debs/*.deb /root/debs/ubuntu18 &&