moves TestScalingUpAndDownSingleNode from cluster-etcd-operator
moves TestScalingUpAndDownSingleNode from cluster-etcd-operator

It tests basic vertical scaling scenario.
The scenario starts by adding a new master machine to the cluster,
next it validates the size of etcd cluster and makes sure the new member is healthy.
The test ends by removing the newly added machine and validating the size of the cluster
and asserting the member was removed from the etcd cluster by contacting MemberList API.

soltysh/origin,deads2k/origin,sallyom/origin,openshift/origin,deads2k/origin,akram/origin,bparees/origin,jsafrane/origin,deads2k/origin,sallyom/origin,jsafrane/origin,mahak/origin,bparees/origin,jsafrane/origin,csrwng/origin,mahak/origin,mfojtik/origin,hroyrh/origin,openshift/origin,soltysh/origin,mahak/origin,mfojtik/origin,akram/origin,openshift/origin,hroyrh/origin,sallyom/origin,akram/origin,bparees/origin,mfojtik/origin,csrwng/origin,hroyrh/origin,soltysh/origin,csrwng/origin