Key Terms end-user documentation

Now that Serval and silnlp will be sharing a common key terms implementation (in Machine), we should document how our tools make use of key terms for draft generation. This would need to include information such as:

• which key terms list types we can process
• which source languages we have glosses for
• what kinds of key terms we will make use of
• the required format for the project-specific renderings in a project's key terms list
• which key terms are most important to render for purposes of drafting (i.e., next book key terms).

An end-user view of this information is needed (i.e., a Scripture Forge / Serval view), as well as a developer view (i.e., an silnlp view).