Prototype of filtered search in FALCONN

This release introduces the very first prototype that adheres to metadata constraints (read: filtered search). The filtering happens only in the Python wrapper, but is a proof of concept.

What's Changed

• Update readme with get started guide by @A-Guldborg in #1
• Filtered search into master by @A-Guldborg in #3

New Contributors

• @A-Guldborg made their first contribution in #1

Full Changelog: https://github.com/duckth/FALCONN/commits/v0.0.1