New board: Elecrow CrowPanel Basic 2.8" (#225)

- Implemented Elecrow CrowPanel Basic 2.8"
- Change default "invert" setting for ILI934x driver from `true` to `false`
- Created `Xpt2046` driver subproject
- Refactored unPhone to use new `Xpt2046` driver subproject

Boards/ElecrowCrowpanelBasic28/Source/hal/CrowPanelTouch.h

@@ -0,0 +1,6 @@
+#pragma once
+
+#include <memory>
+#include <Xpt2046Touch.h>
+
+std::shared_ptr<Xpt2046Touch> createTouch();