Merge pull request #583 from magento-falcons/MAGETWO-60647

Fixed issues:
- MAGETWO-60647: Delivery of bug fixes for Sample Data and Import/Export
- MAGETWO-56787: [GITHUB][PR] Added call to action to compile command error #4134
- MAGETWO-56786: [GITHUB][PR] Ensure composer.json exists #4121
- MAGETWO-57799: cannot upgrade 2.0 => 2.1 with auto_increment > 1
- MAGETWO-59715: Impossible to import additional_images with labels which have a comma separator
- MAGETWO-60633: [Github] .htaccess deny code execution not working for Apache + php-fpm #6766
- MAGETWO-46636: Nginx doesn't redirect to setup page when using port