add drum-machine-react

drum-machine-react/src/SelectionLeft.js

@@ -0,0 +1,17 @@
+import React from 'react';
+
+import Selection from "./Selection";
+import SelectVolume from "./SelectVolume";
+import Metronome from "./Metronome";
+
+const SelectionLeft = () => {
+  return (
+    <div id="selection-left">
+      <Selection />
+      <SelectVolume />
+      <Metronome />
+    </div>
+  );
+}
+
+export default SelectionLeft;