Removes unused combineOjects function
Merge branch 'master' into preprelease
Some improvements

o Adds bef.options(download_dir="dir") used in the download now
  also chooses a sensible default download directory so it does
  not clutter the working directory
o Adds the attachment download to the wrapper so this is now
  available:
	bef.portal.get.attachment(dataset_id=7)
	bef.portal.get(dataset_id=7, attachment=T)