Add possibility to set current patch as default one

Added button (icon TODO) in toolbar to save the current patch into
template.vcv (instead of having to know that we must save it with this
name)

include/app.hpp

@@ -170,6 +170,7 @@ struct RackWidget : OpaqueWidget {
 	/** Disconnects all wires */
 	void disconnect();
 	void save(std::string filename);
+	void setAsDefaultPatch();
 	void load(std::string filename);
 	json_t *toJson();
 	void fromJson(json_t *rootJ);

src/app/RackScene.cpp

@@ -95,6 +95,12 @@ void RackScene::onHoverKey(EventHoverKey &e) {
 					e.consumed = true;
 				}
 			} break;
+			case GLFW_KEY_D: {
+				if (windowIsModPressed() && windowIsShiftPressed()) {
+					gRackWidget->setAsDefaultPatch();
+					e.consumed = true;
+				}
+			} break;
 			case GLFW_KEY_V: {
 				if (windowIsModPressed() && !windowIsShiftPressed()) {
 					gRackWidget->pastePresetClipboard();

src/app/RackWidget.cpp

@@ -139,6 +139,11 @@ void RackWidget::save(std::string filename) {
 	json_decref(rootJ);
 }
 
+void RackWidget::setAsDefaultPatch() {
+	info("Saving current patch as default one in 'tempalte.vcv'");
+	save(assetLocal("template.vcv"));
+}
+
 void RackWidget::load(std::string filename) {
 	info("Loading patch %s", filename.c_str());
 	FILE *file = fopen(filename.c_str(), "r");

src/app/Toolbar.cpp

@@ -69,6 +69,16 @@ struct SaveAsButton : TooltipIconButton {
 	}
 };
 
+struct SetAsDefaultPatchButton : TooltipIconButton {
+	SetAsDefaultPatchButton() {
+		setSVG(SVG::load(assetGlobal("res/icons/noun_1343811_cc.svg")));
+		tooltipText = "Set patch as default (" WINDOW_MOD_KEY_NAME "+Shift+D)";
+	}
+	void onAction(EventAction &e) override {
+		gRackWidget->setAsDefaultPatch();
+	}
+};
+
 struct RevertButton : TooltipIconButton {
 	RevertButton() {
 		setSVG(SVG::load(assetGlobal("res/icons/noun_1084369_cc.svg")));
@@ -170,6 +180,7 @@ Toolbar::Toolbar() {
 	layout->addChild(new OpenButton());
 	layout->addChild(new SaveButton());
 	layout->addChild(new SaveAsButton());
+	layout->addChild(new SetAsDefaultPatchButton());
 	layout->addChild(new RevertButton());
 	layout->addChild(new DisconnectCablesButton());