Add additional setup instructions to README (#55)

Issue #, if available:

Description of changes:

This adds additional details for how to deploy the ACK service controller for RDS, including examples for creating database instances using the PostgreSQL and MariaDB engines.

By submitting this pull request, I confirm that my contribution is made under
the terms of the Apache 2.0 license.

Author: jkatz

README.md

@@ -1,26 +1,45 @@
 # ACK service controller for Amazon Relational Database Service (RDS)
 
-This repository contains source code for the AWS Controllers for Kubernetes
-(ACK) service controller for Amazon RDS.
+This repository contains source code for the AWS Controllers for Kubernetes (ACK) service controller for Amazon RDS.
 
-Please [log issues][ack-issues] and feedback on the main AWS Controllers for
-Kubernetes Github project.
+Please [log issues](https://github.com/aws-controllers-k8s/community/issues) and feedback on the main AWS Controllers for Kubernetes Github project.
+
+## Overview
+
+The ACK service controller for Amazon Relational Database Service (RDS) provides a way to manage RDS database instances directly from Kubernetes. This includes the following database engines:
+
+* [Amazon Aurora](https://aws.amazon.com/rds/aurora/) (MySQL & PostgreSQL)
+* [Amazon RDS for PostgreSQL](https://aws.amazon.com/rds/postgresql/)
+* [Amazon RDS for MySQL](https://aws.amazon.com/rds/mysql/)
+* [Amazon RDS for MariaDB](https://aws.amazon.com/rds/mariadb/)
+* [Amazon RDS for Oracle](https://aws.amazon.com/rds/oracle/)
+* [Amazon RDS for SQL Server](https://aws.amazon.com/rds/sqlserver/)
+
+The ACK service controller for Amazon RDS provides a set of Kubernetes [custom resource definitions](https://kubernetes.io/docs/concepts/extend-kubernetes/api-extension/custom-resources/) for interfacing with the [Amazon RDS API](https://docs.aws.amazon.com/AmazonRDS/latest/APIReference/) through a declarative Kubernetes workflow. This lets you to run your applications in Kubernetes with a fully-managed relational database in RDS.
+
+## Getting Started
+
+To learn how to [get started with the ACK service controller for Amazon RDS](https://aws-controllers-k8s.github.io/community/docs/tutorials/rds-example/), please see the [tutorial](https://aws-controllers-k8s.github.io/community/docs/tutorials/rds-example/).
+
+## Help & Feedback
+
+The ACK service controller for Amazon RDS is based on the [Amazon RDS API](https://docs.aws.amazon.com/AmazonRDS/latest/APIReference/). To get a full understanding of how all of the APIs work, please review the [Amazon RDS API documentation](https://docs.aws.amazon.com/AmazonRDS/latest/APIReference/).
+
+You can learn more about [how to use Amazon RDS](https://docs.aws.amazon.com/rds/index.html) through the [documentation](https://docs.aws.amazon.com/rds/index.html).
+
+For [general help with ACK](https://github.com/aws-controllers-k8s/community#help--feedback), please see the [ACK community README](https://github.com/aws-controllers-k8s/community#help--feedback).
 
-[ack-issues]: https://github.com/aws-controllers-k8s/community/issues
 
 ## Contributing
 
 We welcome community contributions and pull requests.
 
-See our [contribution guide](/CONTRIBUTING.md) for more information on how to
-report issues, set up a development environment, and submit code.
-
-We adhere to the [Amazon Open Source Code of Conduct][coc].
+See our [contribution guide](https://github.com/aws-controllers-k8s/rds-controller/blob/main/CONTRIBUTING.md) for more information on how to report issues, set up a development environment, and submit code.
 
-You can also learn more about our [Governance](/GOVERNANCE.md) structure.
+We adhere to the [Amazon Open Source Code of Conduct](https://aws.github.io/code-of-conduct).
 
-[coc]: https://aws.github.io/code-of-conduct
+You can also learn more about our [Governance](https://github.com/aws-controllers-k8s/rds-controller/blob/main/GOVERNANCE.md) structure.
 
 ## License
 
-This project is [licensed](/LICENSE) under the Apache-2.0 License.
+This project is [licensed](https://github.com/aws-controllers-k8s/rds-controller/blob/main/LICENSE) under the Apache-2.0 License.