I think our track docs make things too complicated for new students.

Right after the required installation of PHP we have a short paragraph about installing composer. For PHPUnit we then describe composer as the main means of installation. Using the PHPUnit PHAR is last and "optional". But composer is not required to solve Exercism exercises.

The easiest way to use PHPUnit for Exercism is downloading the PHAR. So we should provide tutorial-style instructions on that first. Also we should check, that exercism test runs the PHAR when using these instructions.

In a more optional looking paragraph we may then describe and explain composer and PHPUnit installation using it. There is a nice short description of composer and installation we may use to improve the composer introduction and installation. We should also mention that composer is wide-spread in the PHP ecosystem.