Add Docker image and compose with documentation

docker.md

@@ -0,0 +1,40 @@
+# vxTwitter Docker
+
+## Configuration
+
+Setup mongodb in `config.json`:
+```json
+{
+    "config":{
+        "link_cache":"db",
+        "database":"mongodb://twitfix_db:27017/",
+        [...]
+    },
+    [...]
+}
+```
+
+Use TCP socket for uwsgi `twitfix.ini`:
+```ini
+[uwsgi]
+module = wsgi:app
+
+master = true
+processes = 5
+
+socket = 0.0.0.0:9000
+buffer-size = 8192
+#socket = /var/run/twitfix.sock
+#chmod-socket = 660
+vacuum = true
+
+die-on-term = true
+```
+
+## Run
+
+To run and build, use this command:
+```bash
+docker-compose up -d --build
+```
+