Handle share links

[half-duplex]

Fixes #8

Test links (from the praw commit, I'm not touching the reddit app):
https://www.reddit.com/r/redditdev/s/WNauetbiNG (submission)
https://www.reddit.com/r/redditdev/s/nGnQE1QkLC (comment)

Example output:

me> https://www.reddit.com/r/redditdev/s/WNauetbiNG
Sopel> [reddit] [PRAW] HTTPS enabled PRAW testing needed ('PRAW' flair) (self.redditdev) | 11 points (84.0%) | 2 comments | Posted by bboe | Created at 2014-09-17 - 06:34:31 UTC | https://redd.it/2gmzqe
me> https://www.reddit.com/r/redditdev/s/nGnQE1QkLC
Sopel> [reddit] Comment by bboe | 1 point | Posted at 2014-09-18 - 03:13:54 UTC | https://reddit.com/comments/2gmzqe/c/cklhv0f | Yes it does. That fix is also in the master branch, we just haven't made a release for it (and we probably won't until 3.0).