Skip settings page if php.exe is as required

This is a first PoC implementation of an idea I had to make the installation less cumbersome:

If the php.exe on the system is already configured as needed (the php version matches requirements and the `php` command is inside `%Path%`), the settings page to select the PHP binary must not be displayed (by default).

The results in one click less and the user must not decide which php.exe to pick if all is okay already.