Updated composer.json to PSR-4 autoloader.

[jaakristioja]

The PSR-0 format has been deprecated in favor of PSR-4. For details, see:

• http://www.php-fig.org/psr/psr-0/
• http://www.php-fig.org/psr/psr-4/
• php-fig/fig-standards@61f2d259

[JeroenDeDauw]

I know the standard is deprecated. What about support for PSR-0 in Composer itself?

[jaakristioja]

Afaik composer has support for both. According to http://www.php-fig.org/psr/psr-4/ both could be used:

It is fully interoperable, and can be used in addition to any other autoloading specification, including PSR-0.

So I guess it should actually be possible to have both "psr-0" and "psr-4" sections in composer.json without them conflicting.

[JeroenDeDauw]

Yes, I know Composer supports both, and that one can use both at the same time. The question is if the PSR-0 support in Composer in deprecated in any way. I know there are big projects, such as Doctrine, which do not like PSR-4 and demand usage of PSR-0 in their package definitions.

For this projects it's fine though, I'll merge once the CI passed.