AWS SAM deployment (#91)

* Generate AWS SAM application
with the Poseidon Java 11 Executor Lambda Function.

* Extend AWS Lambda documentation.

* Apply suggestions from code review

Co-authored-by: Sebastian Serth <MrSerth@users.noreply.github.com>

* Parse dynamic AWS region

Co-authored-by: Sebastian Serth <MrSerth@users.noreply.github.com>

deploy/aws/README.md

@@ -0,0 +1,44 @@
+# Poseidon AWS Executors
+
+This project contains source code and supporting files for a serverless application that you can deploy with the SAM CLI. It includes the following functions.
+
+- java11ExecFunction - Code for the application's Lambda function. It can execute Java files with JDK 11.
+- events - Invocation events that you can use to invoke the function.
+- template.yaml - A template that defines the application's AWS resources.
+
+The application uses several AWS resources, including Lambda functions and an API Gateway API. These resources are defined in the `template.yaml` file in this project. You can update the template to add AWS resources through the same deployment process that updates your application code.
+
+See the [AWS SAM developer guide](https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/what-is-sam.html) for deployment, usage and an introduction to SAM specification, the SAM CLI, and serverless application concepts.
+
+## Interface
+
+You can establish a WebSocket connection to the WebSocketURI generated by the deployment. With this connection you can send requests to the lambda functions following this interface:
+
+```
+action:
+  description: The name of the requested function.
+  type: string
+cmd:
+  description: The command that should be executed.
+  type: []string
+files:
+  description: The files that will be copied before the execution.
+  type: map[string]string
+```
+
+So for example:
+```
+{
+  "action": "java11Exec",
+  "cmd": [
+    "sh",
+    "-c",
+    "javac org/example/RecursiveMath.java && java org/example/RecursiveMath"
+  ],
+  "files": {
+    "org/example/RecursiveMath.java":"cGFja2FnZSBvcmcuZXhhbXBsZTsKCnB1YmxpYyBjbGFzcyBSZWN1cnNpdmVNYXRoIHsKCiAgICBwdWJsaWMgc3RhdGljIHZvaWQgbWFpbihTdHJpbmdbXSBhcmdzKSB7CiAgICAgICAgU3lzdGVtLm91dC5wcmludGxuKCJNZWluIFRleHQiKTsKICAgIH0KCiAgICBwdWJsaWMgc3RhdGljIGRvdWJsZSBwb3dlcihpbnQgYmFzZSwgaW50IGV4cG9uZW50KSB7CiAgICAgICAgcmV0dXJuIDQyOwogICAgfQp9Cgo="
+  }
+}
+```
+
+The messages sent by the function use the [WebSocket Schema](../../api/websocket.schema.json).