Pretty print XML
Cleanup.
Progress bar update
Download resume improvements.

- Set correct Range
- Validate respnse status
- Validate Content-Range

 #104
Improved Content-Range parsing.

  #104
Added Content-Range parsing tests.

  #104
Cleanup
Cleanup
Improved progress bar (#104).
Performance and progress bar improvements.

  #104
Handle KeyboardInterrupt while --download'ing (#104).
Used Content-Disposition filename (#104).
Tests
Added support for output redirection with --download (#104).
--download docs (#104).
Cleanup
Docs fix.
Only use Range when already have a partial download.
Validate download options before setting up streams.
Cleanup