Delete dead code

I can find no sign that the code in these files is used for anything anywhere

core/src/main/java/info/openrocket/core/file/configuration/XmlContainerElement.java

@@ -1,23 +0,0 @@
-package info.openrocket.core.file.configuration;
-
-import java.util.ArrayList;
-import java.util.List;
-
-public class XmlContainerElement extends XmlElement {
-
-	private final ArrayList<XmlElement> subelements = new ArrayList<XmlElement>();
-
-	public XmlContainerElement(String name) {
-		super(name);
-	}
-
-	public void addElement(XmlElement element) {
-		subelements.add(element);
-	}
-
-	@SuppressWarnings("unchecked")
-	public List<XmlElement> getElements() {
-		return (List<XmlElement>) subelements.clone();
-	}
-
-}

core/src/main/java/info/openrocket/core/file/configuration/XmlContentElement.java

@@ -1,27 +0,0 @@
-package info.openrocket.core.file.configuration;
-
-/**
- * A simple XML element that contains textual content.
- * 
- * @author Sampo Niskanen <sampo.niskanen@iki.fi>
- */
-public class XmlContentElement extends XmlElement {
-
-	private String content = "";
-
-	public XmlContentElement(String name) {
-		super(name);
-	}
-
-	public String getContent() {
-		return content;
-	}
-
-	public void setContent(String content) {
-		if (content == null) {
-			throw new IllegalArgumentException("XML content cannot be null");
-		}
-		this.content = content;
-	}
-
-}

core/src/main/java/info/openrocket/core/file/configuration/XmlElement.java

@@ -1,43 +0,0 @@
-package info.openrocket.core.file.configuration;
-
-import java.util.HashMap;
-import java.util.Map;
-
-/**
- * A base simple XML element. A simple XML element can contain either other XML
- * elements
- * (XmlContainerElement) or textual content (XmlContentElement), but not both.
- * 
- * @author Sampo Niskanen <sampo.niskanen@iki.fi>
- */
-public abstract class XmlElement {
-
-	private final String name;
-	private final HashMap<String, String> attributes = new HashMap<String, String>();
-
-	public XmlElement(String name) {
-		this.name = name;
-	}
-
-	public String getName() {
-		return name;
-	}
-
-	public void setAttribute(String key, String value) {
-		attributes.put(key, value);
-	}
-
-	public void removeAttribute(String key) {
-		attributes.remove(key);
-	}
-
-	public String getAttribute(String key) {
-		return attributes.get(key);
-	}
-
-	@SuppressWarnings("unchecked")
-	public Map<String, String> getAttributes() {
-		return (Map<String, String>) attributes.clone();
-	}
-
-}

core/src/main/java/module-info.java

@@ -40,7 +40,6 @@ open module info.openrocket.core {
 	exports info.openrocket.core.document.attachments;
 	exports info.openrocket.core.document.events;
 	exports info.openrocket.core.file;
-	exports info.openrocket.core.file.configuration;
 	exports info.openrocket.core.file.iterator;
 	exports info.openrocket.core.file.motor;
 	exports info.openrocket.core.file.openrocket;
@@ -106,4 +105,4 @@ open module info.openrocket.core {
 			info.openrocket.core.optimization.services.DefaultOptimizableParameterService;
 	provides info.openrocket.core.optimization.services.SimulationModifierService with
 			info.openrocket.core.optimization.services.DefaultSimulationModifierService;
-}
+}