Option to Ignore Model::preventLazyLoading for 3rd party or specific packages

[ziming]

Model::preventLazyLoading() is a really nice feature, however sometimes we can't do much about it when the lazy loading code is in a 3rd party package.

It will be nice if we can enable preventLazyLoading but ignore if the lazy loading code is in a package or in a list of packages we specified to ignore. Something like a flag we can pass into this method if possible.