Change reference initializations errors in GCC 4.8

Resolves issue #12.

firmware/application/main.cpp

@@ -281,8 +281,8 @@ public:
 		ui::Painter& painter,
 		ui::Context& context
 	) : top_widget { top_widget },
-		painter { painter },
-		context { context }
+		painter(painter),
+		context(context)
 	{
 		// touch_manager.on_started = [this](const ui::TouchEvent event) {
 		// 	this->context.focus_manager.update(this->top_widget, event);

firmware/application/receiver_model.hpp

@@ -35,7 +35,7 @@ class ReceiverModel {
 public:
 	constexpr ReceiverModel(
 		ClockManager& clock_manager
-	) : clock_manager { clock_manager }
+	) : clock_manager(clock_manager)
 	{
 	}
 

firmware/application/ui_console.hpp

@@ -38,7 +38,7 @@ public:
 		const Rect parent_rect,
 		lcd::ILI9341& display
 	) : Widget { parent_rect },
-		display { display }
+		display(display)
 	{
 	}
 

firmware/application/ui_navigation.cpp

@@ -119,7 +119,7 @@ SystemView::SystemView(
 	Context& context,
 	const Rect parent_rect
 ) : View { parent_rect },
-	context_ { context }
+	context_(context)
 {
 	style_ = &style_default;
 

firmware/application/ui_receiver.cpp

@@ -376,7 +376,7 @@ void LNAGainField::on_focus() {
 ReceiverView::ReceiverView(
 	NavigationView& nav,
 	ReceiverModel& receiver_model
-) : receiver_model { receiver_model }
+) : receiver_model(receiver_model)
 {
 	add_children({ {
 		&button_done,