Docker (#2867)

* Dockerize Misskey

* Add a new line at EOF

* Add support Elasticsearch

* /

* Add setup document for docker

* Add english document

* Edit docs

* docker -> Docker

* Arrange format

* Update docker.en.md

* Modify title

.gitignore

@@ -1,5 +1,6 @@
 /.config/*
 !/.config/example.yml
+!/.config/mongo_initdb_example.js
 /.vscode
 /node_modules
 /build
@@ -12,3 +13,6 @@ npm-debug.log
 run.bat
 api-docs.json
 *.log
+/redis
+/mongo
+/elasticsearch