This causes a failure during image download. Scenario:
- import dicom folder,
- go to dataset and select all images in the middle panel (so they also get highlighted in the tree viewer),
- only possibility to download all is through the right-click context menu in tree viewer - do that,
- if any images already existed in the target directory, code throws:
    

        java.lang.Exception: java.io.IOException: Destination '/Users/bpindelski/Desktop/ankle.dcm' already exists
          at org.apache.commons.io.FileUtils.moveFile(FileUtils.java:1811)
          at org.apache.commons.io.FileUtils.moveFileToDirectory(FileUtils.java:1856)
          at org.openmicroscopy.shoola.env.data.views.calls.ArchivedImageLoader.copyFile(ArchivedImageLoader.java:78)