Third Korean l10n work for release 1.18

- Translate cluster-administration/networking.md in Korean
- Fix issue with concepts/storage/volumes.md
- Translate /concepts/configuration/pod-overhead in Korean
- Update to Outdated files in the dev-1.18-ko.3 branch.
- Translate concepts/configuration/configmap.md in Korean
- Translate contribute/review/reviewing-prs/ in Korean
- Translate concepts/configuration/pod-priority-preemption.md in Korean
- Translate tasks/configure-pod-container/configure-volume-storage in Korean
- Translate contribute/new-content/new-content/ in Korean
- Translate concepts/architecture/control-plane-node-communication.md in Korean
- Restore the deleted master-node-communication.md file
- Translate concepts/cluster-administration/addons.md in Korean
- Translate contribute/new-content/overview/ in Korean
- Translate tasks/tools/install-kubectl.md in Korean
- Translate concepts/configuration/manage-resources-containers.md in Korean
- Translate tasks/administer-cluster/kubeadm/kubeadm-upgrade/ in Korean
- add new words to Korean glossary and fix minor
- Translate contribute/style/_index.md in Korean
- Translate concepts/cloud-administration/cloud-providers.md in Korean
- Translate contribute/review/for-approvers.md in Korean

Co-authored-by:    Jerry Park <jaehwa@gmail.com>
Co-authored-by:    Seokho Son <shsongist@gmail.com>
Co-authored-by:    jmyung <jesang.myung@gmail.com>
Co-authored-by:    coolguyhong <podolsmith@naver.com>
Co-authored-by:    Yuk, Yongsu <ysyukr@gmail.com>
Co-authored-by:    bluefriday <bluefriday86@gmail.com>
Co-authored-by:    SangshikLee <neolss@gmail.com>

content/ko/docs/reference/glossary/pod.md

@@ -4,7 +4,7 @@ id: pod
 date: 2018-04-12
 full_link: /ko/docs/concepts/workloads/pods/pod-overview/
 short_description: >
-  가장 작고 단순한 쿠버네티스 오브젝트. 파드는 사용자 클러스터에서 동작하는 컨테이너의 집합을 나타낸다. 
+  파드는 클러스터에서 실행 중인 컨테이너의 집합을 나타낸다.
 
 aka: 
 tags: