Firefox on iOs is detected as Safari

[janmech]

When checking for firefox the first criteria to is the absence of 'safari' in the user agent string.

but on iOS 'safari' appears (@see: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/User-Agent/Firefox)

Instead of 'Firefox/version' 'FxiOS/version' is used.

Hence firefox on iOS is identified as Safari with version:unkown.

IN:

Sinergi\BrowserDetector\BrowserDetector

public static function checkBrowserFirefox()
    {
        if (stripos(self::$userAgentString, 'safari') === false) {
            if (preg_match("/Firefox[\/ \(]([^ ;\)]+)/i", self::$userAgentString, $matches)) {
                if (isset($matches[1])) {
                    self::$browser->setVersion($matches[1]);
                }
                self::$browser->setName(Browser::FIREFOX);

                return true;
            } elseif (preg_match('/Firefox$/i', self::$userAgentString, $matches)) {
                self::$browser->setVersion('');
                self::$browser->setName(Browser::FIREFOX);

                return true;
            }
        }

        return false;
    }

[derpoho]

Looks like #86 !

Can somebody merge this PR?