Step how to go back to previous Woocommerce for those who are not ready to make update with the new Woocommerce:
1. Make sure you have a backup of your previous woocommerce plugin which you downloaded as backup using FTP or from your Cpanel. If you have the backup, you are ready to go. If not then I suggest to use sweetmoses method as he prescribe above. Never try that before, so I don't know the end result, especially with your products data, etc.
2. First, deactivate your newly updated wooceommerce plugin.
3. Using FTP go to your Woocommerce plugin and erase all files of the newly updated woocommerce plugin. You don't have to delete the Woocommerce folder though, only whats inside the folder which was previously updated.
4. Next, go to your backup plugin files in your computer. Find woocommerce folder, go inside that folder, then copy paste or select and drag all the files to the empty woocommerce folder on your live site.
5. After its done copying, go to your plugin page then active again the woocommerce plugin. It will still show the "Your theme has bundled outdated copies of WooCommerce template files – if you encounter functionality issues on the frontend this could the reason. Ensure you update or remove them (in general we recommend only bundling the template files you actually need to customize). See the system report for full details." ... just hide it :) since it will keep telling you to make the update. It works for me :) So I will not give any guarantee if you want to use the method I prescribe above.
6. Last but not least, if maybe you are not aware or ready on how to make a woocommerce plugin update, which can be of various reasons of which in this case I suggest Woocommerce should also make an options for their user to roll back to previous version of woocommerce, just incase some people might need that, since people need time to make any adjustment to ask for a theme compatibility adjustment to their developer or because of other reasons which maybe occured, while on the same time their site need to run normally. Anyway, the woocommerce plugin update is really a good thing for us, but if I may suggest is that plugin developers should also aware that some WordPress users are novice in technicality and some might only end users who accidentally press the update button and "ups ...".
7. I also suggest that users who were not familiar with updating plugin should not make an update before reading what will the plugin do to your site in a whole. Just make sure you know what you are doing. My best suggestion is to make regular backup of the database and all the files, before making any wordpress, plugin or theme update.
I hope it helps. Thanks