ui: basic search view

- Added a basic SearchView (+ controller and qt implementation)
- SearchView can set the active element of other views by dispatching a message.
- SearchView adjusts its text when the active element is changed by other views.
- Added wrappers for Button and EditBox that allow the usage of simple callback functions.

src/lib/component/controller/CodeController.h

@@ -17,7 +17,9 @@ struct AnnotatedText
 	Id tokenId;
 };
 
-class CodeController: public Controller, public MessageListener<MessageActivateToken>
+class CodeController
+	: public Controller
+	, public MessageListener<MessageActivateToken>
 {
 public:
 	CodeController(std::shared_ptr<LocationAccess> locationAccess);