A little code cleanup and photo post conversion enhancement

[AmritPatel]

There were a few bugs likely introduced by changes either in Python or the Tumblr API so I fixed those first to get it to run.

For the photo post type, I modified your script so that all photos are added to post body instead of just the first one. This change was motivated by me wanting to incorporate my old Tumblr photo blog into my newest statically hosted one using Hugo. After a few minor changes, it worked like a charm! Thank you so much for your efforts!

I leave this pull request here for you to merge for the benefit of those who might stumble upon your work and find it useful like myself.

Cheers, Amrit