Update inflections.php

[zesda]

• Throw an Exception when attempting to call require on a file that might not exist - addresses issue raised in FR: Unavailable locales #33

[coveralls]

Coverage decreased (-0.5%) to 91.86% when pulling 8b6b654 on zesda:master into fb6ca79 on ICanBoogie:master.

[olvlvl]

Hi @zesda, thanks for your contribution. I recently updated the requirements for PHP 7.1+. Could you rebase your branch and add a test for the changes introduced?