FORMAT: use jsonnet for templating

* add jsonnet templates
* rewrite all charts to jsonnet

_templates/argo_helm_app.template

@@ -0,0 +1,30 @@
+# vim:ft=jsonnet:
+local base = import "argo_base.template";
+
+base + {
+	repo:: error "repo must be defined",
+	chart:: $.name,
+	version:: error "version must be defined",
+	skipCrds:: false,
+	values:: "",
+
+	spec+: {
+		source+: {
+			repoURL: $.repo,
+			chart: $.chart,
+			targetRevision: $.version,
+		}
+
+		+ (
+		if std.length($.values) > 0 then
+		{ helm+: { values: $.values } } else {}
+		)
+
+		+ (
+		if $.skipCrds then
+		{ helm+: { skipCrds: true } } else {}
+		)
+
+	}
+
+}