Move chart to a subdirectory for easier usage with helm-git

contrib/charts/espresso/.helmignore

contrib/charts/espresso/Chart.yaml

contrib/charts/espresso/templates/NOTES.txt

contrib/charts/espresso/templates/_helpers.tpl

contrib/charts/espresso/templates/configmap.yaml

contrib/charts/espresso/templates/deployment.yaml

contrib/charts/espresso/templates/hpa.yaml

contrib/charts/espresso/templates/ingress.yaml

contrib/charts/espresso/templates/service.yaml

contrib/charts/espresso/templates/serviceaccount.yaml

contrib/charts/espresso/templates/tests/test-connection.yaml

contrib/charts/espresso/values.yaml