Fwdpy11

Fix 1105 via 1106

Bug fix

* Fix error in conditional models when sampling ancient
samples throughout the focal mutation sojourn.
PR 1094
Issue 1093

Bug fix in the new implementations of binomial crossover types released in 0.19.4

PR 1088

Massive improvement to the performance of simulations using genetic maps with a large number of PoissonInterval classes.

**These changes mean that simulations with many regions will give different results for the same random number seed.**

1087 (see issue 1082)

This release also include several back-end changes getting ready to use demes models directly.
See the detailed change log in the manual.

Deprecations

* The low-level Python API for defining demographic events
is now deprecated and will raise warnings.
No action has to be taken yet.
There is no replacement API to migrate to.
PR {pr}`1064`.

Back end changes

* Prepare to refactor C++ code to evolve directly from `demes` graphs.
PR {pr}`1063`.
PR {pr}`1067`.
* Boolean flags affecting simulation behavior collected into `struct`.
PR {pr}`1061`.

Documentation

* Add link between vignettes regarding
importing tree sequences from tskit.
PR {pr}`1054`.
* Force notebooks to be executed during doc builds.
PR {pr}`1058`.

Testing/CI

* Docs workflow updated to run with Python 3.10.
PR {pr}`1056`.