Delete CollectionUtils (unused)

src/main/java/fr/xephi/authme/util/Utils.java

@@ -2,6 +2,7 @@ package fr.xephi.authme.util;
 
 import fr.xephi.authme.ConsoleLogger;
 
+import java.util.Collection;
 import java.util.regex.Pattern;
 
 /**
@@ -50,6 +51,16 @@ public final class Utils {
         }
     }
 
+    /**
+     * Null-safe way to check whether a collection is empty or not.
+     *
+     * @param coll The collection to verify
+     * @return True if the collection is null or empty, false otherwise
+     */
+    public static boolean isCollectionEmpty(Collection<?> coll) {
+        return coll == null || coll.isEmpty();
+    }
+
     /**
      * Return the available core count of the JVM.
      *