Resolve "Add fast recalbox settings manager"

Please make sure your MR is ready to be merged !

• You added the changes in CHANGELOG.md
• You described the MR as below
• You updated the recalbox wiki
• You wrote a blog post on recalbox-blog

Changes :

• Add recalbox-settings package that compiles a recalbox_settings executable. The new executable is full compatible with the python script's parameters. Key loading takes less than 20ms on RPi0.
• Replace all python calls (in RPi0/1 environement since this is the most critical)

Closes #876 (closed)