Bump version to 0.1.1 (PRQL#302)

* Bump version to 0.1.1

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Improve cli docstring (PRQL#240)