v0.4.0

Version 0.4.0 of the kairos library.
There was a code refactoring as well as cleanup contributed. Also
dependencies were updated by that contributor. They asked me to release
this as 0.4.0, which I am gladly doing with this release.
-----BEGIN SSH SIGNATURE-----
U1NIU0lHAAAAAQAAADMAAAALc3NoLWVkMjU1MTkAAAAggOWMm6Tkty/JixDvs4tQ7/H5V0
1v+BgdjLb2Dmz9X80AAAADZ2l0AAAAAAAAAAZzaGE1MTIAAABTAAAAC3NzaC1lZDI1NTE5
AAAAQO08YyZHIUzPWQrnwcwmHnAYMQm8qp9GGWondcSml5wSxQ6qsIXAZ3AgRU0/i8CBoR
i4Neh1L6MXUPO3R3dajwo=
-----END SSH SIGNATURE-----