chore: Upgrade `babel` related packages. (#646)
chore: Upgrade `babel` related packages. (#646)

* `babel-cli@6.26.0`
* `babel-eslint@7.2.3`
* `babel-register@6.26.0`
* `babel-runtime@6.26.0`
* `babel-preset-env@1.6.1`

This is mostly to get babel parsing support for some of the newer flow features, before we introduce flow typing to the tedious source code.
pekim/tedious,tediousjs/tedious,tediousjs/tedious