ded8bdb238
* Retitle to use StatefulSet term * Use full name: Apache Cassandra * Always use StatefulSet from apps/v1 * (It's safe to assume readers are using Kubernetes ≥ v1.9) * Update to match website style guidelines * Move note about environment variables out of overview * Tweak wording for clarity & tidy whitespace * Tweak chained shell commands for clarity * Drop duplicated / unnecessary task prerequisites