Added some tests

lib/src/main/java/rife/render/DateIso.java

@@ -21,7 +21,6 @@ import rife.template.Template;
 import rife.template.ValueRenderer;
 import rife.tools.Localization;
 
-import java.text.DateFormat;
 import java.time.ZonedDateTime;
 import java.time.format.DateTimeFormatter;
 

lib/src/main/java/rife/render/SwapCase.java

@@ -40,6 +40,7 @@ public class SwapCase implements ValueRenderer {
      * @param src the String to swap the case of
      * @return the modified String or null
      */
+    @SuppressWarnings("PMD.AvoidReassigningLoopVariables")
     public static String swapCase(final String src) {
         if (src == null || src.isEmpty()) {
             return src;