xpath: Fix code formatting and comments

Author: bertrand-lorentz

src/main/java/eu/europa/ted/eforms/xpath/XPathInfo.java

@@ -4,7 +4,7 @@
 import java.util.List;
 
 public class XPathInfo {
-	private LinkedList<XPathStep> steps = new LinkedList<>();
+  private LinkedList<XPathStep> steps = new LinkedList<>();
   private String pathToLastElement;
   private String attributeName;
 

src/main/java/eu/europa/ted/eforms/xpath/XPathListenerImpl.java

@@ -125,8 +125,8 @@ public void exitAbbrevforwardstep(AbbrevforwardstepContext ctx) {
    * because {@link ParserRuleContext#getText()} omits whitespace and other lexer tokens in the
    * HIDDEN channel.
    *
-   * @param context
-   * @return
+   * @param context Information on a rule that matched
+   * @return The input text that matched the rule corresponding to the specified context
    */
   private String getInputText(ParserRuleContext context) {
     return this.inputStream

src/main/java/eu/europa/ted/eforms/xpath/XPathStep.java

@@ -13,15 +13,15 @@ public class XPathStep implements Comparable<XPathStep> {
   private final List<String> predicates;
 
   public XPathStep(String stepText, List<String> predicates) {
-		this.stepText = StringUtils.strip(stepText);
+    this.stepText = StringUtils.strip(stepText);
     this.predicates = predicates;
-	}
+  }
 
   public String getStepText() {
     return stepText;
   }
 
-	public List<String> getPredicates() {
+  public List<String> getPredicates() {
     return predicates;
   }