WISHLIST: allow documentation of a package's internal features as well

[mon-key]

I've written a lightly tested version of manifest which allows for also
returning the internally documented features of a package.
It is available here: http://github.com/mon-key/manifest

It works by adjusting the internal heuristics of manifest::names and adding the
keyword INCLUDING-INTERNALS to the lambda listof following to include the
defaulted &key parameter (including-internals including-internals) and
adjusting the arglist to their callers accordingly:

manifest::names
manifest::manifest
manifest::package-page
manifest::needs-documentation
manifest::documentation-templates