♻️ Favor method_missing over a raft of delegates

[jeremyf]

It's like we're flooding a political convention with delegates. Instead of having all of those delegate methods, let's just implement method missing and pass things along to the SolrDocument.

The benefit is that as we incorporate dynamic metadata, we don't need to keep on adding delegate :this_property, to: :solr_document.

@samvera/hyrax-code-reviewers

[dlpierce]

I like this. I was surprised to still need to customize the presenter (and other files) when we have the metadata schema yaml files in place. However, I'm going to wait until after 5.0.1 to merge this.