Support of metadata as an XML-file

[vkush]

Add to exportElement method and test it with DV/DS:

case REPLACE:
				if (deposit.getEntryPart() != null) {
					// Use "replace" method for EntryPart (metadata as a Map)
					SwordResponse response = swordClient.replace(collectionURL, deposit, authCredentials);
					return response;
				} else {
					// Use "replace" for Media (metadata as a XML-file)
					// TODO: create issue for SWORD-Client to consider the header "In-Progress:
					// true" for "replaceMedia()" method
					// -> https://github.com/swordapp/JavaClient2.0/issues
					//
					// Code area, file "org.swordapp.client.SWORDClient.java", lines 464-468:
					//
					// // add the headers specific to a binary only deposit
					// http.addContentDisposition(options, deposit.getFilename());
					// http.addContentMd5(options, deposit.getMd5());
					// http.addPackaging(options, deposit.getPackaging());
					// http.addMetadataRelevant(options, deposit.isMetadataRelevant());
					//
					// Add new line:
					// http.addInProgress(options, deposit.isInProgress());
					//
					SwordResponse response = swordClient.replaceMedia(collectionURL, deposit, authCredentials);
					return response;
				}

If works for DS/DV -> create issue in Java SWORDClient, see comments inside the code above.