strict comparison for getting array value by key

[sethphillips]

When getting errors, loose equality sometimes matches the 0 index of the array of errors and not the nested 'Errors' key. This results in an index 'Number' not found exception on $this->setErrorCode($errorInfo['Number']);

[denizozsen]

+1 from me for this change! I was about to create a pull request for the same issue.

[denizozsen]

@sethphillips @VinceG While not strictly necessary, I would also suggest to use a strict equality check in line 439, to allow for fetching falsy values like 0, false, empty array, etc. I know this is not used right now, but could cause some head scratching in the future.

I.e. this:

        if ($return = $this->getValueByKey($each, $key)) {
            return $return;
        }

would become this:

        $return = $this->getValueByKey($each, $key);
        if ($return !== null) {
            return $return;
        }