Cassandre trading bot framework 5.0.6 released

A new version is here

- Allow strategy update.
- Refactor archetypes to make them more simple.
- Improve message errors on startup.
- Better Readme and search engine added to the website.
- Documentation improved & migration to vuepress v2.
- GraphQL API documentation was added to the website.
- Improve continuous integration process.
- Libraries updates (including XChange 5.0.12).