minor #3188 AppVeyor - add PHP 7.x (keradus, julienfalque)
minor #3188 AppVeyor - add PHP 7.x (keradus, julienfalque)

This PR was submitted for the master branch but it was squashed and merged into the 2.11 branch instead (closes #3188).

Discussion
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AppVeyor - add PHP 7.x

it will fail most probably...
let us treat it as TODO

Commits
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d3f56960 AppVeyor - add PHP 7.x

GrahamCampbell/PHP-CS-Fixer,FriendsOfPHP/PHP-CS-Fixer,Slamdunk/PHP-CS-Fixer,gharlan/PHP-CS-Fixer,SpacePossum/PHP-CS-Fixer,FriendsOfPHP/PHP-CS-Fixer,keradus/PHP-CS-Fixer,kubawerlos/PHP-CS-Fixer,keradus/PHP-CS-Fixer,SpacePossum/PHP-CS-Fixer,GrahamCampbell/PHP-CS-Fixer,kubawerlos/PHP-CS-Fixer,Slamdunk/PHP-CS-Fixer,gharlan/PHP-CS-Fixer