v3.1.0

Signed and notarized. Recommended: download the .dmg, open
it, and drag Readr into Applications. The .zip is the same app
for scripted installs.

What's Changed

• Fix the four read-aloud breakers, and wire Kokoro as Readr Voice (beta) by @Anusree-J in #79

Full Changelog: v3.0.0...v3.1.0