Add wrapper for kubectl

Use k8s wait method and scale wait times to remove flakiness

Fix bug to allow riofile export to have multiples

Also add stack to rm types in CLI

Bump serving max-scale-up-rate to allow scaling

Automation scale and run tests

- Porting run tests from python to go spec.
- Adding scale up to 3, 5 and 10 scale tests.
- Removing python CI scripts from executing.

Add ability to provide imagePath in Riofile

Move to go testing

Currently this acts as a max rate, rather than max over tick-interval.
Bringing this inline with the upstream changes:
https://github.com/knative/serving/pull/4527/commits/4b0c4ffd0ff0bf6b2a5912960ca4c8c0ed2902ec

Use of kubectl instead of an alias

fix typo

In order to onboard devs and the community faster we are unifying
the codebase into go. We are also moving towards BDD style specs so
that the tests are more human readable, and our current suite (and its
gaps) are more immediately obvious.

Update README with slack info

Update readme for slack info

README update: route insert is a flag on add, not standalone

Doc changes for v0.5.0

Switch ingress to extension api

Fix wrong mixer naming

Swap name and namespace in router docs

Fix lite install being broken in istio mesh mode

Fix lite install paramaters being broken due to the wrong parameters and
template patterns.

Print subcommand help 

Update with linkerd metric fix, fix scale to zero bug