Only print progress ticker every 5 chunks. Don't print progress ticker if in an emacs shell. Return a list of filenames for failed downloads in `Item.download()` rather than True/False.
Only print progress ticker every 5 chunks. Don't print progress ticker if in an emacs shell. Return a list of filenames for failed downloads in `Item.download()` rather than True/False.

brycedrennan/internetarchive,jjjake/internetarchive,JesseWeinstein/internetarchive