Added null-check for lore

src/main/java/eu/ruekov/ruakij/LinkedBeaconTeleporters/linkedBeaconTeleporter/LinkedBeaconTeleporterManager.java

@@ -152,9 +152,11 @@ public class LinkedBeaconTeleporterManager {
     String serialiseBeaconItem(String name, List<String> lore){
         // get name and remove control-chars
         String str = name.replace("\\", "\\\\");
-        for (String loreLine : lore) {
-            // get lore-lines and remove control-chars
-            str += "\n"+ loreLine.replace("\\", "\\\\");
+        if(lore != null){
+            for (String loreLine : lore) {
+                // get lore-lines and remove control-chars
+                str += "\n"+ loreLine.replace("\\", "\\\\");
+            }
         }
 
         return str;