Implemented AlertDialog app (#117)

Tactility/Source/app/alertdialog/AlertDialog.h

@@ -0,0 +1,23 @@
+#pragma once
+
+#include <string>
+#include <vector>
+#include "Bundle.h"
+
+/**
+ * Start the app by its ID and provide:
+ *  - a title
+ *  - a text
+ *  - 0, 1 or more buttons
+ */
+namespace tt::app::alertdialog {
+
+    void start(std::string title, std::string message, const std::vector<std::string>& buttonLabels);
+
+    /**
+     * Get the index of the button that the user selected.
+     *
+     * @return a value greater than 0 when a selection was done, or -1 when the app was closed clicking one of the selection buttons.
+     */
+    int32_t getResultIndex(const Bundle& bundle);
+}