Split out the Package type into a first class Kubernetes resource. Before this change, packages were implicitly tied to functions.
This wasn't ideal because:
* Functions will need to share packages
* A package storage system may be more generally useful than just
functions (for example, for storing static assets)
This change does the following:
* Updates the fission and tpr types to add a new Package and PackageSpec. It also creates a PackageRef type, and a FunctionPackageRef type. The PackageRef simply references a package, but the FunctionPackageRef includes the name of a function within the package. This allows us to share packages between different functions.
* Updates fetcher and other components for first-class packages
* Allows customization of fetcher image pull policy in the helm charts
Remove hardcoded "fission" namespace in various places.
Remove etcd deployment and service, since we use K8s APIs now.
Add ClusterRoleBinding for the fission service account, to allow fission components to access TPRs. We currently make the service account a cluster admin. This is more permissive than it should be; we should define a specific role for just fission resources.
Improve fission helm chart; split it into "fission core" and "fission all". fission-core is the minimal install, and fission-all will have all the bells and whistles.
* Update/Add fission-core & fission-all helm charts
* Fix incompatible types for comparison
* Add message queue trigger
* Rename openshiftRBAC to openshift
* Update documentation & comments
* Fix logger & kubewatcher failed to access kubernetes resource due to RBAC
