Use correct default DB URL

Dockerfile

@@ -2,16 +2,6 @@ FROM ubuntu:16.04
 MAINTAINER Bartosz Ptaszynski <foobarto@gmail.com>
 MAINTAINER Marcin Kulik <support@asciinema.org>
 
-# A quickstart:
-#
-#     docker run -d -p 5432:5432 -e POSTGRES_USER=asciinema -e POSTGRES_PASSWORD=sekrit --name=postgres postgres
-#     docker run -d -p 6379:6379 --name=redis redis
-#     docker run --rm -e DATABASE_URL="postgresql://asciinema:sekrit@postgres/asciinema" asciinema/asciinema.org bundle exec rake db:setup
-#     docker run -d -e DATABASE_URL="postgresql://asciinema:sekrit@postgres/asciinema" asciinema/asciinema.org bundle exec sidekiq
-#     docker run -d -e DATABASE_URL="postgresql://asciinema:sekrit@postgres/asciinema" -p 3000:80 asciinema/asciinema.org
-#
-# You can override the address/port that is sent in email with login token by passing HOST="host:port" environment variable when starting the web server.
-
 ARG DEBIAN_FRONTEND=noninteractive
 ARG NODE_VERSION=node_6.x
 ARG DISTRO=xenial
@@ -111,7 +101,7 @@ RUN cd a2png && lein cljsbuild once main && lein cljsbuild once page
 
 COPY . /app
 
-ENV DATABASE_URL "postgresql://asciinema:sekrit@postgres/asciinema"
+ENV DATABASE_URL "postgresql://postgres@postgres/postgres"
 ENV REDIS_URL "redis://redis:6379"
 
 # compile terminal.c