Moved former ListCell#updateItem methods into separate Control objects

Additionally fixed bug showing wrong color of infoLabel after switching
scenes

src/main/resources/css/base.css

@@ -3,7 +3,7 @@
 }
 
 .context-menu, .context-menu > * {
-	-fx-background-radius: 15px;
+	-fx-background-radius: 15.0px;
 	/*TODO: solution below does not work */
 	-fx-background-color: transparent;
 }
@@ -58,3 +58,19 @@
 	-fx-text-fill: #00FF00;
 	-fx-background-color: transparent;
 }
+
+#infoLabel-success {
+	-fx-text-fill: #00FF00;
+}
+
+#infoLabel-info {
+	-fx-text-fill: yellow;
+}
+
+#infoLabel-warning {
+	-fx-text-fill: orange;
+}
+
+#infoLabel-error {
+	-fx-text-fill: red;
+}