Expose Sequelize lib

[ekryski]

So that end users don't need to require it separately we should just expose the underlying sequelize lib. Just in case people need access to it.

[daffl]

I don't think this is necessary (or even possible). You only have to supply the initialized model. The plugin itself doesn't directly depend on Sequelize at all.

[ekryski]

Right. Sequelize gets initialized outside of the adapter.