Thoughts on the new Help customization framework

Created by: dregad

In 3.0, the library allows 2 methods to customize the output of getHelpText:

• via a class implementing GetOpt\HelpInterface, or
• by writing custom template scripts, similar to those provided in resources/

I hope you won't mind my saying so, but I'm not very keen on the proposed approach, particularly the second one, and I think this should be improved. Here's a few issues I see:

1. having to create up to 3 custom templates (even as copies of the provided ones) and maintain them is cumbersome
2. there is some code and logic in the original templates which would be nice to be able to reuse as-is in custom ones
3. Some of this logic is duplicated (e.g. the console width detection is both in options.php and commands.php
4. let's say I want to keep the standard template, but localize the output; I can't do that easily because some strings are hardcoded

The custom Help class is better, but still does not allow easy reuse of code in the default templates.

A couple of suggestions for improvement:

• instead of relying on standalone PHP scripts for templates and using output buffering to capture their output, let the setXxxTemplate() methods accept a callable instead, and put the contents of the script into methods of the Help class which will return a string instead of echoing.
• extract duplicated code into helper methods, to be used as building bricks for the callable
• provide a way to localize the output

Let me know your thoughts.