Allow ANGULAR_TOKEN_OPTIONS to be used (#461)

Author: rmorlok

projects/angular-token/src/public_api.ts

@@ -11,6 +11,8 @@ export {
   AngularTokenOptions
 } from './lib/angular-token.model';
 
+export { ANGULAR_TOKEN_OPTIONS } from './lib/angular-token.token';
+
 export { AngularTokenService } from './lib/angular-token.service';
 
 export { AngularTokenModule } from './lib/angular-token.module';