create CDC event stream CRD (#1570)

* provide event stream API
* check manifest settings for logical decoding before creating streams
* operator updates Postgres config and creates replication user
* name FES like the Postgres cluster
* add delete case and fix updating streams + update unit test
* check if fes CRD exists before syncing
* existing slot must use the same plugin
* make id and payload columns configurable
* sync streams only when they are defined in manifest
* introduce applicationId for separate stream CRDs
* add FES to RBAC in chart
* disable streams in chart
* switch to pgoutput plugin and let operator create publications
* reflect code review and additional refactoring

Co-authored-by: Paŭlo Ebermann <paul.ebermann@zalando.de>

pkg/util/constants/streams.go

@@ -0,0 +1,14 @@
+package constants
+
+// PostgreSQL specific constants
+const (
+	EventStreamCRDApiVersion     = "zalando.org/v1"
+	EventStreamCRDKind           = "FabricEventStream"
+	EventStreamCRDName           = "fabriceventstreams.zalando.org"
+	EventStreamSourcePGType      = "PostgresLogicalReplication"
+	EventStreamSourceSlotPrefix  = "fes"
+	EventStreamSourcePluginType  = "pgoutput"
+	EventStreamSourceAuthType    = "DatabaseAuthenticationSecret"
+	EventStreamFlowPgGenericType = "PostgresWalToGenericNakadiEvent"
+	EventStreamSinkNakadiType    = "Nakadi"
+)