Remove insecure and deprecated gconf dependency on linux.

Gconf has been deprecated and unmaintained for years, along with some of its dependencies, like python 2.7 (which reached end of life at the new year), and the launcher wont run without it. This is dangerous, as there could be hidden security vulnerabilities in both gconf and python 2.7. The new suggested alternatives are dconf and gsettings. Python versions at or lower than 2.7.16 (which are still installed on many systems) are affected by CVE-2019-9948