[docs] Add CI matrix and script (#5461)

.gitlab-ci/packet.yml

docs/_sidebar.md

docs/ci.md

tests/files/packet_centos7-weave-kubeadm-sep.yml

tests/files/packet_oracle7-canal.yml

tests/files/packet_ubuntu16-canal-ha.yml

tests/files/packet_ubuntu16-canal-kubeadm.yml

tests/files/packet_ubuntu16-contiv-sep.yml

tests/files/packet_ubuntu16-flannel-ha.yml

tests/files/packet_ubuntu16-kube-router-sep.yml

tests/files/packet_ubuntu16-weave-sep.yml

tests/scripts/md-table/main.py

tests/scripts/md-table/requirements.txt

tests/scripts/md-table/table.md.j2

tests/scripts/md-table/test.sh

tests/scripts/md-table/tmp.md