Merge branch 'jm/status-ignored-files-list'

Merge branch 'jm/status-ignored-files-list'

The set of paths output from "git status --ignored" was tied
closely with its "--untracked=<mode>" option, but now it can be
controlled more flexibly.  Most notably, a directory that is
ignored because it is listed to be ignored in the ignore/exclude
mechanism can be handled differently from a directory that ends up
to be ignored only because all files in it are ignored.

* jm/status-ignored-files-list:
  status: test ignored modes
  status: document options to show matching ignored files
  status: report matching ignored and normal untracked
  status: add option to show ignored files differently