add FormRow component; rename unwrapped components with underscore

src/components/FormRow.jsx

@@ -0,0 +1,15 @@
+import React from 'react';
+
+export default function FormRow ({ children }) {
+  return (
+    <div
+      style={{
+        display: 'grid',
+        gridGap: '20px',
+        gridTemplateColumns: 'repeat(auto-fit, minmax(300px, 1fr))'
+      }}
+    >
+      {children}
+    </div>
+  );
+}