Improve doc generation for nested elements

[VillePihlava]

Is your feature request related to a problem? Please describe.

For example, when using the asEnumMap function to create configuration objects, generating the documentation can cause duplicate entries. The entries also specify a mode in the path, which can be misleading when the functions could also affect all modes. See the attached picture:

OpenTripPlanner/application/src/main/java/org/opentripplanner/standalone/config/framework/json/ParameterBuilder.java

Line 305 in e9a8742

public <T, E extends Enum<E>> Map<E, T> asEnumMap(

Goal / high level use-case

The doc generation should be changed to enable removing the misleading duplicate entries and mode information.