Thanks to:

+ Sergiusz Bazanski a fix in the contrib/setup-* scripts in 2019.

+ Nina Engelhardt for fixing --stop-first handling in btormc in 2020.

+ Marco Gario for fixing a race condition in the build system in 2018.

+ Felix Griesau for a fix in the contrib/setup-* scripts in 2020.

+ Jannis Harder for fixing instructions and scripts for building Boolector for
  64-bit Windows in 2020.

+ Andrew V. Jones for
  - setting up a patch set for building Boolector for Windows in 2019
  - fixes in contrib/setup-* scripts and the build system in 2019
  - adding termination support for CaDiCaL in 2019
  - fixing instructions and scripts for building Boolector for 64-bit Windows
    in 2020
  - providing a Dockerfile for Boolector in 2020
  - fixes/additions in Boolector's C and Python API in 2019 and 2020
  - fixing #136 in 2020