Change disliked and liked to downvoted and upvoted

[justcool393]

Reddit recently changed the URLs for /user//disliked/ and /user//liked/.
reddit-archive/reddit@35339be

[bboe]

Thanks for the effort. This PR is incomplete however as it only is updating the eviction urls. Would you like to update the endpoints for get_liked and get_disliked as well?

[justcool393]

Added. https://reddit.com/user/PyAPITestUser2/upvoted seems to be set to private, so it got 403s when trying to get it.

[bboe]

Thanks for the update. It looks like there are some lint issues, and some of the test cassettes need to be updated. Can you take a look at those?

https://travis-ci.org/praw-dev/praw/jobs/63743280

To run the tests locally execute: python setup.py test. If you have any questions please do not hesitate to ask.

[bboe]

@justcool393 thanks for the effort to make the change. PR #429 was a bit more complete so decided to merge that one in. I look forward to any further contributions you have.