test(kernel/metavar): add metavar tests
test(kernel/metavar): add metavar tests

Signed-off-by: Leonardo de Moura <7610bae85f2b530654cc716772f1fe653373e892@microsoft.com>

UlrikBuchholtz/lean,leodemoura/lean,Kha/lean,fpvandoorn/lean,fpvandoorn/lean2,soonhokong/travis_test,rlewis1988/lean,soonhokong/lean-windows,soonhokong/lean,digama0/lean,johoelzl/lean,c-cube/lean,johoelzl/lean,eigengrau/lean,leodemoura/lean,UlrikBuchholtz/lean,avigad/lean,soonhokong/travis_test,Kha/lean,fpvandoorn/lean,leanprover-community/lean,fpvandoorn/lean2,johoelzl/lean,leanprover/lean,c-cube/lean,johoelzl/lean,leanprover/lean,levnach/lean,Kha/lean,fpvandoorn/lean,digama0/lean,fgdorais/lean,soonhokong/lean-osx,leodemoura/lean,rlewis1988/lean,sp3ctum/lean,soonhokong/lean-osx,rlewis1988/lean,soonhokong/lean-osx,htzh/lean,soonhokong/lean-windows,leanprover-community/lean,eigengrau/lean,UlrikBuchholtz/lean,johoelzl/lean,leanprover/lean,sp3ctum/lean,eigengrau/lean,soonhokong/lean,fgdorais/lean,Kha/lean,dselsam/lean,avigad/lean,avigad/lean,digama0/lean,javra/lean,fpvandoorn/lean,soonhokong/lean-windows,rlewis1988/lean,levnach/lean,c-cube/lean,fpvandoorn/lean2,soonhokong/lean-windows,soonhokong/lean,soonhokong/lean-windows,soonhokong/travis_test,dselsam/lean,leanprover/lean,htzh/lean,eigengrau/lean,leodemoura/lean,levnach/lean,htzh/lean,digama0/lean,avigad/lean,Kha/lean,leanprover-community/lean,fpvandoorn/lean,soonhokong/lean-osx,javra/lean,htzh/lean,eigengrau/lean,javra/lean,johoelzl/lean,soonhokong/lean,leanprover-community/lean,fgdorais/lean,fgdorais/lean,soonhokong/travis_test,fpvandoorn/lean2,digama0/lean,c-cube/lean,digama0/lean,dselsam/lean,Kha/lean,soonhokong/lean,leodemoura/lean,leanprover-community/lean,fgdorais/lean,UlrikBuchholtz/lean,UlrikBuchholtz/lean,sp3ctum/lean,leanprover-community/lean,leodemoura/lean,rlewis1988/lean,dselsam/lean,levnach/lean,soonhokong/lean-osx,sp3ctum/lean,htzh/lean,fpvandoorn/lean,fgdorais/lean,c-cube/lean,avigad/lean,levnach/lean,dselsam/lean,leanprover/lean,sp3ctum/lean,fpvandoorn/lean2,rlewis1988/lean,javra/lean,dselsam/lean,leanprover/lean,avigad/lean,javra/lean