mariadb in productcatalogservice

[foxish]

Adds real mariadb and deployment

[daniel-de-vera]

I would be nice to integrate the deployment of the helm-manifests with skaffold (let skaffold take care of installing those helm charts).
If not, at least update README.md and set running ./helm-manifests/deploy.sh as a prerequisite.

[daniel-de-vera]

In README.md we have:

microservices-demo/README.md

Lines 71 to 73 in ebdb0c2

	- **Minikube** requires you to run a command to access the frontend service:
	```shell
	minikube service frontend-external

But the frontend-external service is commented out:

microservices-demo/kubernetes-manifests/frontend.yaml

Lines 92 to 103 in ebdb0c2

	#apiVersion: v1
	#kind: Service
	#metadata:
	# name: frontend-external
	#spec:
	# type: LoadBalancer
	# selector:
	# app: frontend
	# ports:
	# - name: http
	# port: 80
	# targetPort: 8080

[daniel-de-vera]

These two files are not in-sync with the plugin itself:

plugins/mariadb/README.md
plugins/mariadb/example-sandbox.yaml

IMO, we should either update or remove them.
I would also rename the base directory from plugins/mariadb to plugins/productcatalog-mariadb

[daniel-de-vera]

Should we include a script or some documentation about how to deploy this in our demo cluster?

[foxish]

I would be nice to integrate the deployment of the helm-manifests with skaffold (let skaffold take care of installing those helm charts).

I'll try to simplify this so helm is not needed, else it adds another dependency.