**Feature**
An additional sub-command to the helmfile binary; helmfile test
**Why**
Helm provides helm test (https://github.com/kubernetes/helm/blob/master/docs/chart_tests.md) as a method to run automated tests post chart install to ensure things are working as they should be.
It would be nice to be able to run something like helmfile test against a particular helmfile in order to run helm tests against all charts/releases defined in the file. Either as part of the sync (i.e. helmfile sync --test) to be ran immediately after the corresponding chart is installed, or as a separate command ran after a sync (i.e. helmfile test).
A chart without tests will exit with a 0 status, so it can be safely ran against any charts.
**Notes**
`--cleanup` (bool) & `--timeout` (default: 300) are available as first class arguments. Additional arguments can be passed to the helm binary as with other sub commands using `--args=`
Resolves#144
`helmfile delete` has been implying `--purge` but it is not the case since this change.
The new behavior is `helmfile delete --purge` to actually purge releases.
Run just `helmfile delete` to delete releases but not purge them.
Resolves#71
This is important for deployments where the chart repo is protected by client cert validation.
helmfile.yaml is extended to support `certFile` and `keyFile`:
```
repositories:
- name: roboll
url: http://roboll.io/charts
certFile: optional_client_cert
keyFile: optional_client_key
```
Everything works the same if you don't provide values for them.
Regarding the implementation, the "helm repo add" command already supports the cert-file and key-file values, so we just have to pass them through.
- Simple copy-paste for the most part from sync job. I had started down
the path of adding in a meta PluginCommand directive and trying to make it
more modular, but in the end there are some small differences between
the execution that were a bit difficult to model and it just got ugly.
Figured keeping it simple would be easier to manage
Dan O'Brien
Mike Eves
Yusuke KUOKA
Cedric Meury
Shane Starcher
Greg Burton
Justin Nauman
rob boll