Moved all the bobbycar gui code into this library

src/accessorinterface.h

@@ -0,0 +1,21 @@
+#pragma once
+
+namespace espgui {
+template<typename T>
+struct AccessorInterface
+{
+    virtual T getValue() const = 0;
+    virtual void setValue(T value) = 0;
+};
+
+//! A special type of AccessorInterface that allows for simple variable read/write operations
+//! Can be used to read and write global settings for example.
+template<typename T>
+struct RefAccessor : public virtual AccessorInterface<T>
+{
+    virtual T& getRef() const = 0;
+
+    T getValue() const override { return getRef(); };
+    void setValue(T value) override { getRef() = value; };
+};
+} // namespace espgui