Issue originally made by @mathiasbynens

Description

https://github.com/babel/babel/blob/master/doc/design/compiler-environment-support.md

Node.js v0.10 and v0.12 are both in maintenance mode as per https://github.com/nodejs/LTS#lts-schedule. IMHO it doesn’t make sense to continue to support them.

Supporting only Node.js v4+ would enable Babel and its dependencies (such as regexpu, the project I work on) to publish code that uses supported ES6 features without transpiling at prepublish.

Developers still using such old versions in their build environment can upgrade to a more recent Node.js version or use the last Babel version that supports their Node.js. (This is also how the jsdom project deals with old Node.js versions.) In other words, no one’s workflow would break because of this.

Similar discussion for the ESLint project: eslint/eslint#4483