fpm.doc-dependency

[amitu]

Some dependencies a package may include only for documenting that package, and others who are importing that package should not download those dependencies.

We would call them doc-dependencies (-- fpm.doc-dependcy: <doc only dependency>).

This requires us to demarcate what documents are part of real package, and what are documentation only. One can argue that documentation docs will not be imported by other packages using this package as a dependency.