Add advanced Decodal example

examples/advanced/profiles.dcdl

@@ -0,0 +1,18 @@
+# Environment-specific patches.
+
+base = {
+  env = "dev";
+  tags = ["decodal", "dev"];
+};
+
+prod = base // {
+  env = "prod";
+  host = "api.internal";
+  feature.limit = 100;
+  tags = ["decodal", "prod"];
+};
+
+disabled = base // {
+  feature.enable = false;
+  tags = ["decodal", "disabled"];
+};