v0.3.1

Version 0.3.1

- The whole logic is wrapped by try, so if plugin is failed, it won't break the whole build
- Add header_message, so header_warning is still there ("‼️ This page is created automatically, all your changes will be overwritten during the next MKDocs deployment. Do not edit a page here ‼️") when you want to add a custom message
- Add upstream_url, so now there is a link to the original page, if it's provided
- Migrate to default python logging lib