Version 3.0.0.dev3

• Add documentation and test bench
  • generate README.md from documentation
• Introduce optional usage of webcrypto browser support
• adjust default configuration when run with mkdocs-material
• fix remember_password behavior
• introduce remember_keys
• test and fix hljs, mermaid2 and arithmatex (MathJax) support
• fix compatibility with mkdocs-static-i18n
• various bug fixes

WARNING: this release (and previouse ones of v3) are not handling search_index_encryption correctly IF mkdoch-static-i18n v1.x is used...