Ergonomic component initialization and access to data containers

[k88hudson-cfa]

As designed, the Context current has no concept of ownership for components.

We want components to be able to do a few different things, including initialize, in the right order and access data containers from Context. Right now the ergonomics of this is not great, i.e. it involves having to call context.get_data_container::<PluginType>(), and it would be nice to figure out a better way to do this.