solvers: Update descriptions
Context
Solver description update.
- Remove implementation language from descriptions, it's hardly relevant for users. Keep it in documentation though.
- Precise that crossword composer does not support pre-filled grids because that is relevant.
- Add that xwords-rs is generally the fastest solver in documentation.
What has changed?
Main Changes
croiseur-solver-*-plugin
Update description.
doc
Update description.