Add googlechrome driver 2.27 for osx

[skabashnyuk]

Content for RepositoryMap.xml

        <driver id="googlechrome">
            <version id="2.27">
                <bitrate thirtytwobit="false" sixtyfourbit="true">
                    <filelocation>https://chromedriver.storage.googleapis.com/2.27/chromedriver_mac64.zip</filelocation>
                    <hash>3ebf455e5f461c8f7cabb825af40205b53fce58b</hash>
                    <hashtype>sha1</hashtype>
                </bitrate>
            </version>
        </driver>

[Ardesco]

The example RepositoryMap.xml has now been updated to the latest versions.

You should always of course specify your own RepositoryMap.xml so you can control which versions are downloaded for you project.