Add build option to docker-compose up and wait for postgres to start

docker/compose#374
docker/compose#693

Author: jbarbuto

README.md

@@ -38,7 +38,9 @@ The steps here only need to be run once.
 
 1. Bring up the development services
 
-         docker-compose up
+         docker-compose up --build
+
+   The `--build` option ensures any new dependencies are included.
 
 1. Open the development API
 

bin/start-api

@@ -1,5 +1,8 @@
 #!/bin/sh
 
-pip install -r requirements.txt -U
+# Wait for postgres to start
+# https://github.com/docker/compose/issues/374
+sleep 3
+
 python manage.py migrate
 gunicorn gettingstarted.wsgi --log-file - --reload --workers 2