Merge branch 'initial-docker-compose' into 'master'

Add redis and initial README.md

See merge request !1

README.md

+# workspace 
+
+This is a local development workspace for Trust Services API backend.
+It uses docker-compose to bootstrap the services and their dependencies.
+
+Each service has its own `.env` file in the [env](./env) directory
+with environment variables which will be injected in its container. 
+
+## Prerequisites
+
+* Install [docker](https://docs.docker.com/engine/install/) and [docker-compose](https://docs.docker.com/compose/install/).
+* [Install Go](https://golang.org/doc/install) and set the
+  [`$GOPATH` variable](https://github.com/golang/go/wiki/SettingGOPATH).
+
+## Setup Workspace
+
+TODO
+
+## 3rd Party Services
+
+#### Redis
+
+The Redis server can be reached at `localhost:6397` from your
+local machine. 
+
+The services access Redis from their containers as `redis:6397`

docker-compose.yml

+version: '3.4'
+
+services:
+  redis:
+    image: "redis:alpine"
+    container_name: redis
+    ports:
+      - "6379:6379"