Bump httpoison to 1.0

[jerodsanto]

👋 we use ueberauth_twitter on changelog.com (repo), thanks!

I'd like to upgrade our site to httpoison 1+, but this dep is locked down a bit so I can't.

This commit upgrades to ~> 1.0, which is what the httpoison readme suggests to do. All tests are green.

I'd also be cool with using >= 0.13 if you'd prefer, but 1.0 appears to be a-ok.

[doomspork]

@jerodsanto have you tested this to ensure it works? If so we can get this merged 👍

For future reference you can do this in your mix file:

{:httpoison, "~> 1.0", override: true}

[jerodsanto]

@doomspork yup, works great! I've never seen the override option, very cool thanks for the knowledge! 💚

[doomspork]

@jerodsanto thank you and you're welcome!