Compatibility with Ivy

[indieNik]

Hi, I am running into issues with this package in Angular 9 using Ivy. Here is the error when building the project:

ERROR in node_modules/ng-push/index.d.ts:3:22 - error NG6002: Appears in the NgModule.imports of AppModule, but could not be resolved to an NgMod
ule class.

This likely means that the library (ng-push) which declares PushNotificationsModule has not been processed correctly by ngcc, or is not compatibl
e with Angular Ivy. Check if a newer version of the library is available, and update if so. Also consider checking with the library's authors to 
see if the library is expected to be compatible with Ivy.

3 export declare class PushNotificationsModule {
                       

[JerryFZhang]

This was the only package blocking me from upgrading to Angular 9, I ended up creating https://www.npmjs.com/package/ng-push-ivy for my own use.