Modernize library and improve tests

[ramsey]

Scope

This pull request sets the minimum required PHP version to 5.6, bringing along with this requirement bump a number of updates, including:

• Set the minimum required version for symfony/process to ^3.0
• Update package autoloading to use PSR-4
• Use -P rather than -O when passing options
• Add PHP CodeSniffer with PSR-2 rules
• Add PHP linting to run during tests
• Convert Travis configuration to use Python environment so we can use virtualenv and the Travis CI container-based build environment to test against multiple versions of Python and Pygments, as well as multiple versions of PHP (see the util/install-php.sh script)
• Add test resources for Pygments versions 1.6, 2.0, 2.1, and 2.2

This incorporates all the work from pull requests #3, #5, #6, #7, #9, and #10. Commit authors and dates for each of these PRs have been maintained in this PR.

This also addresses and fixes issues #1, #2, #4, and #8.

Version 2.0.0 Recommendation

If you choose to merge this PR, I recommend releasing the next version as 2.0.0, since the 1.x series supports PHP 5.3.2+ and symfony/process 2.3, and this PR makes the leap to PHP 5.6+ and symfony/process 3.0.

Communication and Maintenance Concerns

I've found this library to be very useful and helpful. However, the lack of movement or responsiveness to any issues or pull requests in over three years is concerning. I'd like to ensure a future for the work you began, and I'm volunteering to help maintain this library.

If I've not heard from you in two weeks, I will begin maintaining a fork of this library at https://github.com/ramsey/pygments. To avoid namespace and package name collisions in the Composer ecosystem, I will change the package name to ramsey/pygments and the namespace name to Ramsey\Pygments. Your copyright notices and the MIT license will remain intact. In the LICENSE file, I will use something similar to this:

Copyright for portions of ramsey/pygments are held by Kazuyuki Hayashi as part
of Pygments.php. All other copyright for ramsey/pygments are held by Ben Ramsey.

Copyright (c) 2013 Kazuyuki Hayashi <hayashi@valnur.net>

Copyright (c) 2017 Ben Ramsey <ben@benramsey.com>

...MIT license...

I will do this only out of need to use this package within other projects and to continue its maintenance and development for others who wish to use it. If I hear from you, I'm more than happy to continue using and contributing to your upstream repository instead.

Thanks! 😄

[coveralls]

Coverage decreased (-0.06%) to 98.276% when pulling 98fa83a on ramsey:2.0 into b3300c3 on kzykhys:master.

[coveralls]

Coverage decreased (-0.06%) to 98.276% when pulling 98fa83a on ramsey:2.0 into b3300c3 on kzykhys:master.

[coveralls]

Coverage decreased (-0.06%) to 98.276% when pulling 98fa83a on ramsey:2.0 into b3300c3 on kzykhys:master.

[coveralls]

Coverage decreased (-0.06%) to 98.276% when pulling 98fa83a on ramsey:2.0 into b3300c3 on kzykhys:master.

[ramsey]

I'm following up to see if you've been able to take a look at this pull request yet. Have you given any thought to my offer to help maintain this library? Looking forward to hearing back. Thanks!

[Krinkle]

@kzykhys @ramsey If you're willing to expand collaborators, sign me up as well. We've adopted this library in MediaWiki and would very much prefer to keep maintaining this as a shared library.

[ramsey]

I hope everything is okay. I'm truly concerned, since I haven't heard anything.

Since I haven't heard back, I've decided to proceed with my fork. I've released version 1.0.0 of ramsey/pygments under the Ramsey\Pygments namespace.

Thanks again for your library! If you'd ever like me to merge anything from my fork into your upstream repository, feel free to let me know. I'm happy to do so.

Best regards!