Pulling the CreateKubeConfig function from the expensive to build
test/utils/apiserver package had a considerable impact on the overall build
time because that package depends on a lot of other packages.
Because only that one function is needed by the framework, that extra build
time can be avoided by moving it into its own package.
This runs etcd and an apiserver using it inside the test process. The caller
can either use the ClientSet or the config file. More options might get added
in the future.
Co-author: Antonio Ojea <antonio.ojea.garcia@gmail.com>