* Various fixes for istio.io tests
- General cleanup of the istio.io testing library
- Include istioctl as a test dependency, which is needed by some of the scripts.
- Add ISTIO_OUT to PATH so that istioctl is available for the tests.
- Restructured istio.io tests to reduce nesting and so that multiple tests can use a common main, which speeds up runtime.
- Use test framework workDir for the location of generated output directories for each test. Previously, output dirs were generated in the source directory.
- Fixing package names to use "_", which is the required separator for go packages.
* Delete istio-demo-auth.yaml