Iterate over resources

[Jammjammjamm]

This branch adds an #each_element method to FHIR::Model so that resources can be easily iterated over.

I also updated some dependencies to address security vulnerabilities.

[arscan]

Not sure if this is a real issue or not, but pry is now giving me this error when I start up the console (I can successfull ignore it now):

fhir_models % bundle exec rake fhir:console
bin/console
require 'pry-coolline' # Failed, saying: undefined method `file' for #<Pry::History:0x00007fd76fcfa398>
Did you mean?  filter

There is a chance this was already in here from a previous update to our Gemfile.lock and I just didn't notice it. Just FYI

[Jammjammjamm]

I saw that too, but I didn't know what to do about it.

[arscan]

Looks good. I also manually verified against a Goal resource from our test data set.

I thought the return value was a little confusing and perhaps it shouldn't be exposed to users (ideally I guess it would return an enumerator or something? or at least that's what each does). No big deal though. Also, I assume that primitive extensions would be ignored here, which might be worth noting in this section of the readme, though we do mention it earlier at a high level too, so I'm ok leaving that out.

I suppose we should backport this to fhir-crucible/fhir_dstu2_models and fhir-crucible/fhir_stu3_models. Hopefully just a copy/paste, but there is a chance that something changed implementaiton-wise that would make this not work? I'm not sure.

[radamson]

Tested it out and everything looks good.

Couple things to discuss regarding the method name and return.

[radamson]

Looks good 👍