Bashou v0.11.0

Changes

• The lesson library opens on your path: the ten lessons to take next, each with its section, and the locked ones about to open. Press f for the whole library, where each section now shows once (git has its own).
• Lessons open by difficulty: the first steps open once you've read the lesson before, most lessons once you've practiced it, and hard ones (C pointers, gdb, Rust, awk and sed, SQL joins, running a CA…) only once you've mastered what comes before.
• systemd is part of the Linux skill now, Linux only, with its lesson, fight and questions. If you had picked systemd, you now learn Linux; your adventure on the systemd road goes on on the Linux one.
• The Snail family is redrawn: a slug builds its shell in a hard hat and hi-vis jacket, brick by brick, until it becomes Gary. Your snail keeps its place in the chain.
• The Snakelet is redrawn as a round-headed baby snake with big eyes.
• Python lessons, questions, fights and projects were reviewed against the official Python docs: files opened with with and an encoding, true facts for Python 3.9, programs run inside their virtual environment, safer hints.
• Keys you type right after Enter, or a half-typed command on a Mac, are no longer lost while the pet makes its room, and Ctrl+C there leaves the terminal as it was.
• In bashou spot, the answers beside a long string stay inside an 80-column terminal.
• A progress file exported with an older Bashou can't be imported any more: update Bashou on both computers, then export again.

Breaking changes

• Breaking change: a pony was told it had to master the lesson before, galloped off to find a teacher and never came back. Bring it home with bashou pony hoof.