Update rendering of OperationDefinition to include the overloads element

[rob-reynolds]

Is:
Given the following:

<OperationDefinition>
...
    <overload>
        <parameterName value="periodStart"/>
        <parameterName value="periodEnd"/>
        <parameterName value="measureId"/>
        <comment value="These are the parameters used to invoke the operation on a type, i.e., URL: [base]/Measure/$evaluate-measure"/>
    </overload>
    <overload>
        <parameterName value="periodStart"/>
        <parameterName value="periodEnd"/>
        <comment value="These are the parameters used to invoke the operation on an instance, i.e., URL: [base]/Measure/[id]/$evaluate-measure"/>
    </overload>
 ...
 </OperationDefinition>

The result of running the publisher does not include the overload information.

Should be:
The overload information is rendered.

There is a full explanation and example in the following Zulip Topic: https://chat.fhir.org/#narrow/stream/179239-tooling/topic/Presentation.20for.20OperationDefinition.2Eoverload

This is related to the publisher issue: HL7/fhir-ig-publisher#412