feat(aws): auto-scaled AWS deployment

Restructure AWS deployment to use load balancers and auto-scaled service
instances.

- This deployment requires a domain to be registered in Route53.
- TLS is relegated to the load balancers. This requires for a
  certificate associate with the registered domain to be created
  inside ACM.
- RDS and EC2 instances now run inside private subnets and are not
  directly accessible by the outside world. A sentinel instance exists
  to provide indirect access, e.g. when setting up the databases.

Signed-off-by: Sergei Trofimov <[email protected]>

.gitignore

@@ -35,3 +35,9 @@ management/cmd/management-service/management-service
 tags
 
 .ipynb_checkpoints
+
+# these are created as part of the build process
+deployments/aws/keycloak/keycloak.conf
+deployments/aws/keycloak/providers
+deployments/aws/keycloak/Dockerfile
+