v0.2.2 Python notebooks and CV dataset conversion.

What's Changed

• [DOC] Update README.md by @jaichopra in #294
• [DUCKDB] Script to upload lance extension zip by @changhiskhan in #295
• [C++] Scan Node reads multiple files by @eddyxu in #300
• [Python] Add lance.util.duckdb to help install the extension transparently by @changhiskhan in #301
• [Python] Notebook fixes by @changhiskhan in #303
• [Python] Make dataset conversion a feature by @changhiskhan in #304

Full Changelog: v0.2.1...v0.2.2