Fixed the path to config.php in the readme file
minor #605 Fixed the path to config.php in the readme file (jaspernbrouwer)

This PR was squashed before being merged into the master branch (closes #605).

Discussion
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Fixed the path to config.php in the readme file

I think the title says it all.

Commits
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415f7d8 Fixed the path to config.php in the readme file