Older Bash would let this get away since the output is used with form:

    read a b <<<$(_pretty__get_caller)

which joined the parts into single line, which happened to be what we
want.

Switch to packaging model where each module goes into separate package.

Such model makes much more sense (after all it's also how big platforms
such as python do it).  It allows better control over dependencies and
allows re-locating modules properly according to compatibility level
(i.e. now exit.sh can go to 'sh' despite the fact that in 'core' it had
to be with other Bash-compatible modules).

Not used anywhere these days

Mostly for consistency with the other two binaries.

'sfdoc' is easier to type and resembles 'pydoc' and 'perldoc' so it's
even easier to remember.

The only purpose of the binary is to show local Shellfu path and it's
in every single Shellfu script.  Let's save people some typing.

Since our package does not install or create anything in /usr/local,
dh_usrlocal won't try to do anything.

Decorate them and treat each argument as separate message (line)

Since __SHELLFU_DIR__ is not known at install time, its value is purely
"theoretical" and we need to be able to override it.

Overview of changes:

 *  Improved and updated README.md

    Actually, the main reason for this update is to make new README
    visible sooner, since it's been significantly improved.  Most
    important change is that the introduction has been moved to own
    document.  Also Installation section has been clarified.  That and
    some tiny fixes.

 *  Made minor visual improvement to mkusage()

 *  Added tests for mkusage() '-w' option

 *  Made SHELLFU_IMPORTED into an internal variable

 *  Added some ShellCheck exceptions

Yep, test suite is growing!

Give more space to packages.

There's no real reason to have it public.

SC2039 - We simply have to use `local` whenever it's possible, and
although it's not defined in POSIX, most common shells do support it
(well, at least Dash, Bash and Zsh).

SC1090 - Sourcing non-constant file is pretty much the main idea of
Shellfu, so avoiding that part does not make sense.

Overview of changes:

 *  Added workaround to shellfu_api test only against own modules

 *  Added option to append clarifying message to usage messages

    Usage messages can now be made more useful by warning user what
    exactly was wrong.  Warnings will appear after the usage message
    and before command exits and decorated with 'bad usage: ' prefix;
    this is so that user will be more likely notice and understand them.

    Note that this could be done earlier by using -E option and adding
    the warning yourself inside usage() function, but the -w option lets
    you keep usage() very simple and yet leads to more consistency.

 *  Codebase maintenance

 *  Refactored charmenu.sh

    The docstring was not very useful so this it was overhauled
    completely.  Also more proper coding style is now in place.

 *  `shellfu` command will now de-duplicate $SHELLFU_PATH

    shellfu init function, and by extension some shellfu-doc modes,
    would list a module twice if its path ended up twice on
    SHELLFU_PATH.  That should no longer happen.

 *  Added mdfmt, a Markdown formatting helper

    This module consists of single function with aim to help generate
    Markdown text from your scripts.

 *  Updated and improved usage-related pretty.sh docstrings

 *  Fixed PRETTY_DEBUG_EXCLUDE double double-underscore bug

    PRETTY_DEBUG_EXCLUDE would not work properly on functions like
    `foo__bar__baz`, where the second double-underscore would make it
    think module name was `foo__bar`, when in fact it's `foo`.

 *  Added journald logging module for pretty.sh

    Using systemd-cat, this module employs journald as way of
    communicating with user.

 *  Added shellfu-sh pseudo-package

    On RPM-based distributions, somebody has to own 'include-sh'
    directory.  Also having shellfu-FOO package helps module packages
    declare their "Shellfu flavor" (ie. `Requires: shellfu-sh` sends
    clear message that a module is "POSIX-oriented".

 *  Updated packaging and meta-data

    Files responsinle for packaging and versioning meta-data have been
    altered to catch up with newer versions of MKit.  This should have
    almost no effect on package (only 'effect' I can think of is a purely
    decorative change in `--version` output).

 *  Fixed typo in SPEC file

    SPEC file claimed that Shellfu is distributed under LGPL2, while
    it's actually GPL3.  (We should consider changing it to LGPL2,
    though.)

 *  Replaced LICENSE file with Markdown version

    Because Markdown is cooler.  For a more serious reason, MKit now has
    *newstub* script, which can help regenerate MKit structure including
    LICENSE file, and this script can only do Markdown (because Markdown
    is cooler).  TL;DR: It will be less hassle to keep MKit stuff fresh.

 *  Updated emnedded TFKit (v0.0.14) and MKit (v0.0.21)

Until TFKit is able to run tests in sandbox (instead of running tests
against installed SUT), this test will throw false positives in case
any other Shellfu modules are present.

This commit adds workaround that should be removed when new TFKit
version is installed.

After usage message, before exiting---that's the sweet spot.

Also a first POSIX-oriented library!

If function name after the module prefix contained double underscore,
the old code would not parse module name properly, e.g.

    foo__bar__baz

would consider 'foo__bar' as module name, when only 'foo' should be
considered.

Used to declare POSIX orientation (in terms od Shellfu), plus to hold
'include-sh' directory on RPM-based distributions.