rename release branch to next

[cball]

I feel like the name release is a little bit confusing, especially as a target branch. If we keep the approach where merging to master creates the release I think it might make more sense to name the default branch next. This way next would contain everything that will be in the next version.

Same concept different name. Thoughts?

[jsjoeio]

Makes sense to me!

Whoever you want to do this (you or me), will you assign that issue to that person?

[jsjoeio]

We'll need to:

• create new branch next from release
• update open PRs to merge into next
• change default branch in Settings
• update CONTRIBUTING
• update branch protection settings
• update PR template to remind people to point to next

[jsjoeio]

I say once we get #24 and #26 merged in, let's tackle this.

[jsjoeio]

Now that I'm thinking about how others do it, I think this makes most sense:

• change release to next
• make master the default. this way, users see it when they come to the repo and then the README and everything will be in sync with what they see on npm
• when we create a new release, we merge next into master

[jsjoeio]

Done via 773d8f9