Bump version to 9.1.3 (#647)

Just as a point of interest, I observed a 3-4% performance improvement
from the BigEnt strategy benchmark as a result of the upgrade to
rustc-hash 2.0. This has zero impact on overall performance.

Bump version to 9.1.2

Regenerate manual

Regenerate manual

V9 Change log and read me (#559)

Co-authored-by: Alejandro González <[email protected]>

Version 8.0.0

Version 7.0.0

Version 6.0.1

Version 6.0.0 (#448)

Version 5.0.1