Merge pull request numba#1647 from pitrou/changelog0231

Changelog for 0.23.1

Merge pull request numba#1621 from pitrou/fix_test_ufuncs

Fix test_ufuncs on some Linux setups

Version 0.22.1

Version 0.22.0

Version 0.21.0

Version 0.20.0

version 0.19.1

Merge pull request numba#1187 from pitrou/relnotes-019

Release notes for 0.19

Version 0.18.2