Updated urllib import to work with Python 3
Replaced oauth2 dependency with requests_oauthlib.
Fixes for Python 3 compat.
Tests Status

Info (test_pytumblr.TumblrRestClientTest) ... ok
test_blogLikes (test_pytumblr.TumblrRestClientTest) ... ok
test_create_audio (test_pytumblr.TumblrRestClientTest) ... ok
test_create_chat (test_pytumblr.TumblrRestClientTest) ... ok
test_create_link (test_pytumblr.TumblrRestClientTest) ... ERROR
test_create_photo (test_pytumblr.TumblrRestClientTest) ... ok
test_create_quote (test_pytumblr.TumblrRestClientTest) ... ok
test_create_text (test_pytumblr.TumblrRestClientTest) ... ok
test_create_video (test_pytumblr.TumblrRestClientTest) ... ok
test_dashboard (test_pytumblr.TumblrRestClientTest) ... ok
test_drafts (test_pytumblr.TumblrRestClientTest) ... ok
test_edit_post (test_pytumblr.TumblrRestClientTest) ... ERROR
test_follow (test_pytumblr.TumblrRestClientTest) ... ERROR
test_followers (test_pytumblr.TumblrRestClientTest) ... ok
test_following (test_pytumblr.TumblrRestClientTest) ... ok
test_info (test_pytumblr.TumblrRestClientTest) ... ok
test_like (test_pytumblr.TumblrRestClientTest) ... ERROR
test_likes (test_pytumblr.TumblrRestClientTest) ... ok
test_no_tags (test_pytumblr.TumblrRestClientTest) ... ok
test_posts (test_pytumblr.TumblrRestClientTest) ... ok
test_posts_with_type (test_pytumblr.TumblrRestClientTest) ... ok
test_posts_with_type_and_arg (test_pytumblr.TumblrRestClientTest) ... ok
test_queue (test_pytumblr.TumblrRestClientTest) ... ok
test_reblog (test_pytumblr.TumblrRestClientTest) ... ERROR
test_submissions (test_pytumblr.TumblrRestClientTest) ... ok
test_tagged (test_pytumblr.TumblrRestClientTest) ... ok
test_unfollow (test_pytumblr.TumblrRestClientTest) ... ERROR
test_unlike (test_pytumblr.TumblrRestClientTest) ... ERROR