Upgrade to aws-java-sdk-s3 1.10.38

This addresses an issue with the SDK providing an incorrect
Content-Type when uploading a multipart part.  Fixes #80.

pom.xml

@@ -262,7 +262,7 @@
     <dependency>
       <groupId>com.amazonaws</groupId>
       <artifactId>aws-java-sdk-s3</artifactId>
-      <version>1.9.28.1</version>
+      <version>1.10.38</version>
       <scope>test</scope>
     </dependency>
     <dependency>

src/test/java/org/gaul/s3proxy/S3AwsSdkTest.java

@@ -228,18 +228,10 @@ public final class S3AwsSdkTest {
                 client.initiateMultipartUpload(initRequest);
         String uploadId = initResponse.getUploadId();
 
-        ObjectMetadata metadata = new ObjectMetadata();
-        metadata.setContentType("application/unknown");
         UploadPartRequest uploadRequest = new UploadPartRequest()
                 .withBucketName(containerName).withKey(key)
                 .withUploadId(uploadId).withPartNumber(1)
                 .withInputStream(byteSource.openStream())
-                // TODO: AWS Java SDK incorrectly provides Content-Type:
-                // application/x-www-form-urlencoded; charset=utf-8
-                // which causes Jetty to parse the HTTP entity as if it
-                // were form-encoded.  With a large upload this exhausts
-                // the Jetty form limit.
-                .withObjectMetadata(metadata)
                 .withPartSize(size);
 
         UploadPartResult uploadPartResult = client.uploadPart(uploadRequest);