Unify Shell-Syntax

kong/content.md

@@ -29,7 +29,7 @@ $ docker run -d --name kong-database \
 Start a PostgreSQL container by executing:
 
 ```shell
-docker run -d --name kong-database \
+$ docker run -d --name kong-database \
                 -p 5432:5432 \
                 -e "POSTGRES_USER=kong" \
                 -e "POSTGRES_DB=kong" \
@@ -41,7 +41,7 @@ docker run -d --name kong-database \
 Run the database migrations with an ephemeral Kong container:
 
 ```shell
-docker run --rm \
+$ docker run --rm \
     --link kong-database:kong-database \
     -e "KONG_DATABASE=postgres" \
     -e "KONG_PG_HOST=kong-database" \