Clg

~~~~~~~~~~~~~~~~~~
* Add some additionnal checks (for the main configuration and types;
`bbcff61 <https://github.com/fmenabe/python-clg/commit/bbcff61>`_,
`dd21371 <https://github.com/fmenabe/python-clg/commit/dd21371>`_).
* Correct a bug where some commands number in the resulted Namespace were skipped
(`6ec1abc <https://github.com/fmenabe/python-clg/commit/6ec1abc>`_).

~~~~~~~~~~~~~~~~~~
* Add subparsers after args and options for improved behaviour
(`4c4471c <https://github.com/fmenabe/python-clg/commit/4c4471c>`_).
* Add a '-p/--page' option to the ``help`` command (added by the
`add_help_cmd <https://clg.readthedocs.io/en/latest/configuration.html#add-help-cmd>`_
parameter) allowing to page the output
(`8b2d9fd <https://github.com/fmenabe/python-clg/commit/8b2d9fd>`_).
* Remove obsolete script for generating bash and zsh completion
(`b7a06fb <https://github.com/fmenabe/python-clg/commit/b7a06fb>`_).
* Fix a bug that prevented the completion (using
`argcomplete <http://argcomplete.readthedocs.io/en/latest/>`_) to work when
``print_help`` is used
(`d2590f7 <https://github.com/fmenabe/python-clg/commit/d2590f7>`_).
* Fix a bug that prevented paging of the help (behaviour induced by the
`page_help <https://clg.readthedocs.io/en/latest/configuration.html#page-help>`_
parameter) when the ``help`` option was not defined manually
(`0a1a0b4 <https://github.com/fmenabe/python-clg/commit/0a1a0b4>`_).
* Add the ``completer`` parameter for options and arguments allowing to manage
`argcomplete completers
<http://argcomplete.readthedocs.io/en/latest/#specifying-completers>`_
(`20c8461 <https://github.com/fmenabe/python-clg/commit/20c8461>`_).
* Update documentation for `argcomplete <http://argcomplete.readthedocs.io/en/latest/>`_
(`66ad52a <https://github.com/fmenabe/python-clg/commit/66ad52a>`_).

~~~~~~~~~~~~~~~~~~
* Add a ``negative_value`` parameter for parsers allowing to redefine how
negatives values are distinguished from options
(`4c7e7be <https://github.com/fmenabe/python-clg/commit/4c7e7be>`_).

~~~~~~~~~~~~~~~~~~
* ``print_help`` parameter is not anymore a root parameter but a per command
parameter and simulate the use of the `--help` option if no arguments are
supplied (`6bee4d9 <https://github.com/fmenabe/python-clg/commit/6bee4d9>`_).
This allows flexibiliy for (sub)commands that do not require any input.

~~~~~~~~~~~~~~~~~~
* Remove empty list for default value when ``nargs`` is set to *\** or *+*
(`4102816 <https://github.com/fmenabe/python-clg/commit/4102816>`_).
* Allows to add custom actions by updating ``ACTIONS`` dictionnary
(`65d7480 <https://github.com/fmenabe/python-clg/commit/65d7480>`_).
* Add a ``page_help`` action allowing to page help
(`818383b <https://github.com/fmenabe/python-clg/commit/818383b>`_,
`f788f35 <https://github.com/fmenabe/python-clg/commit/f788f35>`_).
* Add the parameter ``page_help`` at the root of the configuration allowing
to page the help of all commands (by replacing the default ``help`` action
by the ``page_help`` action;
`9454f7a <https://github.com/fmenabe/python-clg/commit/9454f7a>`_).
* Add the parameter ``print_help`` at the root of the configuration
allowing to print help when no arguments is set (also work for subcommands;
`5ea6fe8 <https://github.com/fmenabe/python-clg/commit/5ea6fe8>`_)

~~~~~~~~~~~~~~~~~~
* Change behaviour of groups: groups now act like parsers rather than just
referencing previously defined options. **It breaks files used by previous
versions**.
* Update design and correct bugs of the ``help`` command added by the
*add_help_cmd* keyword.
* Improve control of abbrevations behaviour. When ``allow_abbrev`` parameter
was activate, it was not possible to concatenate single options or split
with an '=' long options. This is now the case.
* Correct a bug with YAML anchors which causes loss of informations (like
the short option).