Gaia is removed from cosmos-sdk repository.
Few changes were required to make sure no packages depend on gaia subpackages.
CI config is amended accordingly.
Unnecessary targets are removed from Makefile.
Simulations run through a lightweight version of gaia renamed to simapp.
Closes: #4104
Following up #4225:
- Move clog into an external repository
- Update devtools Makefile.
- Add .clog.yaml file required by clog's latest version.
Closes: #4222
Federico Kunze
Alexander Bezobchuk
Alessio Treglia