message: Only adding a slash to destUri if folderName does not already have it
  This should fix
diff: @@ -195,7 +195,7 @@ function uploadFiles (fetcher, files, fileBase, imageBase, successHandler) {
  }
  }
  var folderName = theFile.type.startsWith('image/') ? imageBase || fileBase : fileBase
  - var destURI = folderName + '/' + encodeURIComponent(theFile.name) + suffix
  + var destURI = folderName + (folderName.endsWith('/') ? '' : '/') + encodeURIComponent(theFile.name) + suffix
  fetcher.webOperation('PUT', destURI, { data: data, contentType: contentType })
  .then(response => {
  