do not fail if a generator property is unknown

Author: Sgitario

core/src/main/java/io/dekorate/Session.java

@@ -166,19 +166,19 @@ public void addConfiguration(Map<String, Object> map, BiConsumer<ConfigurationGe
       String key = entry.getKey();
       Object value = entry.getValue();
       ConfigurationGenerator generator = configurationGenerators.get(key);
-      if (generator == null) {
-        throw new IllegalArgumentException(
-            "Unknown generator '" + key + "'. Known generators are: " + configurationGenerators.keySet());
-      }
-
-      if (value instanceof Map) {
-        Map<String, Object> generatorMap = new HashMap<>();
-        Class configClass = configtypes.get(key);
-        String newKey = configClass.getName();
-        Generators.applyPrimitives(configClass, (Map<String, Object>) value);
-        Generators.populateArrays(configClass, (Map<String, Object>) value);
-        generatorMap.put(newKey, value);
-        consumer.accept(generator, Maps.kebabToCamelCase(generatorMap));
+      if (generator != null) {
+        if (value instanceof Map) {
+          Map<String, Object> generatorMap = new HashMap<>();
+          Class configClass = configtypes.get(key);
+          String newKey = configClass.getName();
+          Generators.applyPrimitives(configClass, (Map<String, Object>) value);
+          Generators.populateArrays(configClass, (Map<String, Object>) value);
+          generatorMap.put(newKey, value);
+          consumer.accept(generator, Maps.kebabToCamelCase(generatorMap));
+        }
+      } else {
+        LOGGER.warning("Unknown generator '" + key + "' will be ignored. "
+          + "Known generators are: " + configurationGenerators.keySet());
       }
     }
   }