* cleanup staking references from types pkg
* check interface on runtime
* fixes
* rename validator set from slashing keeper
* final cleanup
* fix test
* fix querier
* fix tests
* rename interfaces
* update bond status
* fixes
* expected pkg
* ensure expected keepers match used funcs
* cha cha cha
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
Alexander Bezobchuk
Marko
Ferenc Fabian
colin axner
frog power 4000
Aayushi Jain
Federico Kunze
Alessio Treglia