==============
- Add configuration variables settable via configuration file, environment
variables, or command line. Display values of variables via new switches
``-show-var VAR``, ``-show-vars``, and ``-show-defaults``.
- Allow for configurable location and type of the main utilities ``find``,
``xargs``, and ``grep``.
- Add ``-ff`` switch for "find files following symlinks"; define ``-ffx`` as
``-stdx -ff``.
- Add ``-grep`` switch to imply ``: <grep> <grep_args> [ :``, where ``<grep>``
is the configuration location for the grep utility and ``<grep_args>`` depends
in a configurable way on the style of the grep utility being used.
- Stop requiring root paths to be directories. POSIX allows roots to be files
as well. Require only that a root exist. Also, relax the restriction that a
path must not have a metacharacter to be considered a root in the absence of
``-root``. Now it is sufficient for the path to exist as-is. This allows
use of shell globbing without worrying whether the globbed paths have
metacharacters in them.
- Decompose ``-stdx`` into ``-stdxd`` (for directories) and ``-stdxf`` (for
files).
- Define variables ``stdxd`` and ``stdxf`` for configuring the globs to exclude
when the corresponding exclusions are active.