Whitespace tweaks

- strip trailing spaces
- correct indentation
Improve support for interrupted downloads

This change ensures that a photo is downloaded again if it's original download
was interrupted (which would have left a zero byte download file on the file
system).
Merge pull request #4 from mocoso/support-for-finishing-incomplete-downloads

Add support for finishing incomplete downloads
Changing "who's" to the correct "whose"
0.3.3
Remove unused method and version bump
indentation