Documentation should include augmentation links

[111pontes]

Documentation for augmentations are included on the augmented model. However, there is a special case where a module defines an augmentation and also defines some data types. In that case, documentation is generated for the data types, but there's no indication of the augmented model. As an example, Cisco_IOS_XR_controller_optics_cfg augments the Cisco_IOS_XR_ifmgr_cfg module, but it only includes documentation about its data types . Having a link to the augmented model will improve usability.
If a module only includes augmentations, we should keep the current behavior for now.