elastic/elasticsearch 23 pull requests

• change default indices.lifecycle.poll_interval to something sane Aug 6
• Whitelisting / from Circuit Breaker Exception (#32325) Aug 7
• Adds explain lifecycle API to the Rest Client Aug 8
• Adds support for move to step action in REST client Aug 8
• Adds REST client support for starting and stopping ILM Aug 9
• HLRC: Ban LoggingDeprecationHandler Aug 9
• move qa yaml tests to inside the ILM plugin Aug 9
• HLRC: Forbid all Elasticsearch logging infra Aug 14
• introduce random timeseries lifecycle policy util method Aug 14
• Add cluster-wide shard limit Aug 14
• add user authentication test for ILM Aug 14
• remove `type` config from LifecyclePolicy JSON Aug 14
• update cluster-state task execution to halt on new phase Aug 15
• remove extraneous CreateIndexRequest context in ShrinkAction Aug 16
• Store phase steps for index in PolicyStepsRegistry Aug 16
• copy LifecyclePolicy to protocol.xpack Aug 16
• Remove PROTO-serialization from IndexMetaData.Custom Aug 16
• conditionally update CS only if StepInfo changes Aug 21
• move ESLoggerFactory usage to LogManager Aug 21
• Have circuit breaker succeed on unknown mem usage Aug 24
• Remove PhaseAfterStep Aug 24
• separate out IndexLifecycleService cluster-state change concerns Aug 27
• HLRC: Add Lifecycle delete to the HLRC Aug 27