BAEL-1821 (#4487)

* Moved Lambda examples to separate module
Implementation of API Gateway example

* Format fixes

* Format fixes

* Minor fixes

* Minor fixes

* Minor fixes

aws-lambda/src/main/java/com/baeldung/lambda/LambdaRequestStreamHandler.java

@@ -0,0 +1,17 @@
+package com.baeldung.lambda;
+
+import com.amazonaws.services.lambda.runtime.Context;
+import com.amazonaws.services.lambda.runtime.RequestStreamHandler;
+import org.apache.commons.io.IOUtils;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+public class LambdaRequestStreamHandler implements RequestStreamHandler {
+
+    public void handleRequest(InputStream inputStream, OutputStream outputStream, Context context) throws IOException {
+        String input = IOUtils.toString(inputStream, "UTF-8");
+        outputStream.write(("Hello World - " + input).getBytes());
+    }
+}