Angular 9.1.0 support

[xmlking]

my build tells angular-in-memory-web-api is not optimized for Angular 9.1.0
would be nice to have this lib updated

Compiling @ngxs/logger-plugin : es2015 as esm2015
Compiling @ngxs/form-plugin : es2015 as esm2015
Compiling @ngxs/storage-plugin : es2015 as esm2015
Compiling @ngxs/router-plugin : es2015 as esm2015
Compiling angular-in-memory-web-api : module as esm5
Compiling ngx-filepond : es2015 as esm2015
Compiling angular-oauth2-oidc : es2015 as esm2015
Compiling ngx-page-scroll : es2015 as esm2015
Compiling ngx-quicklink : es2015 as esm2015
Compiling ngx-perfect-scrollbar : es2015 as esm2015
Generating ES5 bundles for differential loading...
ES5 bundle generation complete.

[darekodz]

I'm waiting for this too

[leantorres73]

Waiting fot this too!