* chore: Add version information of eventing
Adding sources.eventing.knative.dev to version info (the only eventing API)
for now as this will be the first one used.
* chore(version): Add grouping for API versions
* fix(version): Displays supported APIs and version
Fixes#404
```
./kn version
Version: v20191017-local-6328a73-dirty
Build Date: 2019-10-17 09:55:55
Git Revision: 6328a73
Supported APIs:
- serving.knative.dev/v1alpha1 (knative-serving v0.8.0)
```
* Removes ServingVersion feeding from ldflags
- hardcodes the supported APIs as they're supposed to be updated when we bump deps
* Fixes typo in e2e tests
* Uses array for deterministic order of printing supported APIs
Navid Shaikh