S3 SymLink fix

The copy source should be the name of the source bucket and key name
of the source object, separated by a slash (/).

AUTHORS

@@ -29,4 +29,5 @@ List of contributors, in chronological order:
 * Clemens Rabe (https://github.com/seeraven)
 * TJ Merritt (https://github.com/tjmerritt)
 * Matt Martyn (https://github.com/MMartyn)
-* Ludovico Cavedon (https://github.com/cavedon)
+* Ludovico Cavedon (https://github.com/cavedon)
+* Petr Jediny (https://github.com/pjediny)

s3/public.go

@@ -393,7 +393,7 @@ func (storage *PublishedStorage) SymLink(src string, dst string) error {
 
 	params := &s3.CopyObjectInput{
 		Bucket:     aws.String(storage.bucket),
-		CopySource: aws.String(filepath.Join(storage.prefix, src)),
+		CopySource: aws.String(filepath.Join(storage.bucket, storage.prefix, src)),
 		Key:        aws.String(filepath.Join(storage.prefix, dst)),
 		ACL:        aws.String(storage.acl),
 		Metadata: map[string]*string{