Fixed the check of the IO verbosity

Symfony Console 2.3+ supports setting higher verbosity levels than VERBOSE so the isVerbose implementation needs to use an inequality rather than an equality for the condition.

Note that running ``phpspec run -v`` or ``phpspec run -vv`` or ``phpspec run -vvv`` will always give you the same output (after this change), because PhpSpec does not take advantage of the extra verbosity levels to add more output.

Before this change, ``phpspec run -vv`` or ``phpspec run -vvv`` would display the non-verbose output (too much verbosity kills the verbosity)
well, I used what made the smaller diff, making it easier to do it (and to see the change). I can switch the order if you want.

But we are already using such Yoda conditions for inequalities elsewhere (for instance [here](https://github.com/phpspec/phpspec/blob/456b0c662313e28cfb7249bf6e96da313b929a6b/src/PhpSpec/Formatter/Presenter/StringPresenter.php#L80)), so we might want to improve it in the whole library separately (Yoda conditions have an advantage for equality to avoid assignments by mistakes but they often make inequalities less readable as the order has more meaning for them).