0.4.3

- [X] Prepare backlog
- [X] Replace local back-end (file implementation) with a RAM database [100%]
- [X] Update README-dev.md about the new db namespace
- [X] Remove some useless new code
- [X] Improve start/stop server policy (one server may sync multiple buffers/boards... and right now, not really taken into account)
- [X] Clean dead code from the implementation switch from implicit disk files db to RAM db [100%]
- [X] Improve start/stop server policy 2
- [X] Some Refactoring
- [X] Version
- [X] Release notes