integrate events into the servers (#1355)

globals/boundary_developer_env.go

@@ -0,0 +1,8 @@
+package globals
+
+const (
+	// BOUNDARY_DEVELOPER_ENABLE_EVENTS defines an envvar that enables events.
+	// Once this feature is generally available, then this envvar will be
+	// deprecated and removed.
+	BOUNDARY_DEVELOPER_ENABLE_EVENTS = "BOUNDARY_DEVELOPER_ENABLE_EVENTS"
+)