FHIRPath cli output should indicate field names and hierarchy

[lmsurpre]

Is your feature request related to a problem? Please describe.
I used the new(ish) FHIRPath cli jar to build up a complex FHIRPath expression.

One thing that would have helped me is to see the names of the fields in the objects that I was getting back as I build up the expression.

For example, while java -jar fhir-path-4.9.0-cli.jar --file bundle.json --path "Bundle.entry.resource.as(Claim) emits the selected resources as list of json objects, an expression like Bundle.entry.resource.as(Claim).item.detail emits a flattened list of just the leaf node values:

$ java -jar fhir-path-4.9.0-cli.jar --file bundle.json --path "Bundle.entry.resource.as(Claim).item.detail"  
http://example.com/fhir/CodeSystem/claim-item-detail-classification
dispensing-fee
1
http://hl7.org/fhir/sid/ndc
...

What I'd really like at this point is to know which fields those are and what, if any, hierarchy they have so that I can continue to expand on the FHIRPath from here.

Describe the solution you'd like
Use the FHIR model's toString for FHIRPath cli output that results from fhir-path FHIRElementNodes.

This approach would also have the benefit of helping users distinguish between FHIRElementNode results and FHIRPath primitive value results.

Describe alternatives you've considered
Use some other columnar output where the field names are listed with their path from the current location in the leftmost column.

path	value
extension.url	http://example.com/fhir/CodeSystem/claim-item-detail-classification
extension.value	dispensing-fee
sequence	1
...	...

Acceptance Criteria

1. GIVEN [a precondition]
   AND [another precondition]
   WHEN [test step]
   AND [test step]
   THEN [verification step]
   AND [verification step]

Additional context

[prb112]

Ran the following examples:

java -jar fhir-path/target/fhir-path-4.9.0-SNAPSHOT-cli.jar --path 'Bundle.entry.request.method' --file fhir-server-test/src/test/resources/testdata/everything-operation/Antonia30_Acosta403.json --pretty

java -jar fhir-path/target/fhir-path-4.9.0-SNAPSHOT-cli.jar --path 'Bundle.entry.request.method' --file fhir-server-test/src/test/resources/testdata/everything-operation/Antonia30_Acosta403.json

Shows field name and value
{
"code": "POST"
}