Adaptation to Python 3, new features, bug fixes

[jtara1]

If possible, please merge this pull request into a new branch.

My fork has been adapted to Python 3. Here's a summary of my changes in my merge-ready branch:

• Python 3 only
• --num cli arg counts by reddit submission rather than individual image from imgur
• file ._history.txt stores last reddit id downloaded tied to local directory, subreddit name, & subreddit sort_type which is used to resume download position on the subreddit when the 3 aforementioned are matched.
• arguments changed
  • <subreddit> will autodetect whether a text file or subreddit name was passed
  • --restart begin downloading from the beginning of the subreddit
  • --subreddit-list srl-filename download from each of the subreddits found in a text file

In addition to these changes there are fixes to the original code.

See my readme for more details https://github.com/jtara1/RedditImageGrab/tree/merge-ready#jtara1-fork

[rachmadaniHaryono]

subreddit file list is a good feature, but it still need a lot improvement.

here is an example how text file can be used as input list.

https://github.com/Bakkingamu/tumblr_image_download_script

it support commenting and category(in our case we can use sort type etc).

try also documenting the function and method. use google doc style or sphinx style. if it goes right, we can build sphinx docs from the project.

[jtara1]

Thanks for all the feedback; these mostly look like small changes. I haven't collaborated on programming projects like much until recently.

[jtara1]

Here's most of the changes @rachmadaniHaryono recommended. In addition there's a critical fix for imgur-downloader, and a new feature, --restart command line interface argument.

Not sure if my readme.md is exactly how you'd like.