Initial Air Freshener plugin implementation

.vscode/tasks.json

@@ -0,0 +1,16 @@
+{
+  "version": "2.0.0",
+  "tasks": [
+    {
+      "type": "cargo",
+      "command": "post",
+      "args": ["build", "--package", "ebu-plug-core"],
+      "problemMatcher": ["$rustc"],
+      "group": {
+        "kind": "build",
+        "isDefault": true
+      },
+      "label": "rust: cargo build"
+    }
+  ]
+}