New: Define multiple mapped categories for Download Clients

Fixes #170

frontend/src/Components/Form/FormInputGroup.js

@@ -16,6 +16,7 @@ import FormInputHelpText from './FormInputHelpText';
 import IndexerFlagsSelectInputConnector from './IndexerFlagsSelectInputConnector';
 import InfoInput from './InfoInput';
 import KeyValueListInput from './KeyValueListInput';
+import NewznabCategorySelectInputConnector from './NewznabCategorySelectInputConnector';
 import NumberInput from './NumberInput';
 import OAuthInputConnector from './OAuthInputConnector';
 import PasswordInput from './PasswordInput';
@@ -68,6 +69,9 @@ function getComponent(type) {
     case inputTypes.PATH:
       return PathInputConnector;
 
+    case inputTypes.CATEGORY_SELECT:
+      return NewznabCategorySelectInputConnector;
+
     case inputTypes.INDEXER_FLAGS_SELECT:
       return IndexerFlagsSelectInputConnector;
 

frontend/src/Components/Form/NewznabCategorySelectInputConnector.js

@@ -31,7 +31,7 @@ function createMapStateToProps() {
       });
 
       return {
-        value,
+        value: value || [],
         values
       };
     }