Add a custom "back" button to refreshable state

- Long press to return to the "home" screen

lib/widget/back.dart

@@ -0,0 +1,27 @@
+/*
+ * A custom implementation of a "Back" button for display in the app drawer
+ *
+ * Long-pressing on this will return the user to the home screen
+ */
+
+import "package:flutter/cupertino.dart";
+import "package:flutter/material.dart";
+
+Widget backButton(BuildContext context) {
+
+  return GestureDetector(
+    onLongPress: () {
+      while (Navigator.of(context).canPop()) {
+        Navigator.of(context).pop();
+      }
+    },
+    child: IconButton(
+      icon: BackButtonIcon(),
+      onPressed: () {
+        if (Navigator.of(context).canPop()) {
+          Navigator.of(context).pop();
+        }
+      },
+    ),
+  );
+}