Documentation tabs should disable or hide if CM Document does not exist

Problem/Motivation

When managing a fieldable entity that is marked as documentable, the "Documentation" tab appears even if a CM Document does not exist. Clicking it results in a 404. In the case of a document that does not exist yet, It would be a better user experience if either:

1. The tab disappeared.
2. The tab was visible, but inactive.
3. Provided a link to CM Document add and the tab turned to "Add Documentation"

Steps to reproduce

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes