Paperai

This release adds the following enhancements and bug fixes:

- Add ability to read index yml (18)
- Switch from mdv to mdv3 to support Python 3.9 (21)
- Add enhanced API for paperai (30)
- Add configurable query threshold, (31)
- Support query negation (32)
- Add search application (33)

This release adds the following enhancements and bug fixes:

- Add pre-trained models to GitHub (19, 27)
- Add Dockerfile (29)

Sync with txtai 2.0 (26)

This release adds the following enhancements and bug fixes:

- Add annotation report (17)

This release adds the following enhancements and bug fixes:

- Allow specifying vector output file (10, 11, 13)
- Build test suite (12)
- Add additional column parameters (14)
- Allow indexing partial datasources (15)
- Add GitHub actions build script (16)

This release addresses the following:

- Remove NLTK dependency (9)