Support excluding multiple platforms.

Summary:
Currently the schema only allows to exclude a single platform (iOS OR Android). There are cases where we need to exclude multiple. This change converts the previous `excludePlatform` string property into an `excludePlatforms` array.

Changelog:
[Internal][Changed] - Added support to exclude multiple platforms in Codegen.

Reviewed By: sammy-SC

Differential Revision: D21426950

fbshipit-source-id: eff36ffa207109274794b4b300bf6313f8286161

Libraries/Components/RefreshControl/PullToRefreshViewNativeComponent.js

@@ -61,5 +61,5 @@ export const Commands: NativeCommands = codegenNativeCommands<NativeCommands>({
 
 export default (codegenNativeComponent<NativeProps>('PullToRefreshView', {
   paperComponentName: 'RCTRefreshControl',
-  excludedPlatform: 'android',
+  excludedPlatforms: ['android'],
 }): HostComponent<NativeProps>);