fix(rds): remove Instance class

packages/@aws-cdk/aws-rds/README.md

@@ -2,6 +2,14 @@
 
 The `aws-cdk-rds` package contains Constructs for setting up RDS instances.
 
+> Note: this package is currently quite limited, as the CDK team is focusing
+> on other use cases first. If your use case is not in the list below, there is
+> no use coming in to the channel to ask "how do I..." because it won't be
+> possible using high-level constructs. You will have to drop down to the
+> CloudFormation resources layer to achieve your use case.
+>
+> If you would like to help improve the state of this library, Pull Requests are welcome.
+
 Supported:
 
 * Clustered databases

packages/@aws-cdk/aws-rds/lib/index.ts

@@ -1,6 +1,5 @@
 export * from './cluster';
 export * from './cluster-ref';
-export * from './instance';
 export * from './props';
 export * from './cluster-parameter-group';
 export * from './rotation-single-user';