Release 1.7.2.3

Notable changes:
 2018-12-09 e164b762 actionless chore(packaging: ubuntu): add control file with deps for Ubuntu 18.10
 2018-12-08 17d0f99f actionless chore(plugins: materia): update submodule (fix theme generation)
 2018-12-07 8fe5141b poison.vm34 Move and rename color palette