* Update `babel-plugin-transform-object-rest-spread` to v6.19.0

The `babel-plugin-transform-object-rest-spread` v6.19.0 update will
allow us to remove the `babel-plugin-transform-es2015-destructuring` and
`babel-plugin-transform-es2015-parameters` as the object rest spread
transform will now work standalone and not require additional tranforms

* Remove unnecessary babel transform plugins from babel-preset-react-app

The `babel-plugin-transform-object-rest-spread` v6.19.0 update makes
these plugins unnecessary, as v6.19.0 can be used stand-alone

Explain the usage of react-jsx-source & react-jsx-self

* Update babel-preset-env to 0.0.8

Changes between 0.0.6 and 0.0.8 should be backwards compatible:
https://github.com/babel/babel-preset-env/blob/master/CHANGELOG.md

* Use `node: 'current'` as target for babel-preset-env

This replaces the hand-rolled node version setup with a new feature that
was introduced in babel-preset-env@v0.0.7

https://github.com/babel/babel-preset-env/blob/v0.0.7/CHANGELOG.md

* Enable babel parameters/destructuring for all versions of Node

* Add more descriptive comment explaining plugin use

* Disable ES2015 transforms based on node version using babel-preset-env

* pass major version number for node to babel-preset-env instead of version string

* use parseFloat() instead of parseInt() to parse node version

* fixed style nits

Fixes #700.
Read about it here: https://twitter.com/dan_abramov/status/779308833399332864.

tagging dev-only code (@remove-on-publish-begin/end) and pre-eject-only code (@remove-on-eject-begin/end) #257 (#257)

This makes generators work with Jest.

Fixes #255.
Replaces #262.

Disabled because of issues:
 * https://github.com/facebookincubator/create-react-app/issues/525
 * https://phabricator.babeljs.io/search/query/pCNlnC2xzwzx/

TODO: Enable again when these issues are resolved.

* Started using babel-preset-latest

* Updated babel dependencies

* Remove redundant babel-plugin-syntax-async-functions

* Disabled redundant regenerator transform

* Transform async functions with regenerator

Remove `transform-async-to-generator`, which to my understanding is meant
to be used in environments that support generators natively.

Because we're compiling generators to ES5 anyway, we can simply use
`regenerator` to transform async functions too, which results in
slightly simpler output and only uses the regenerator runtime instead
regenerator runtime + _asyncToGenerator Babel helper.

* Add babel-plugin-transform-regenerator

* Use dependencies with an exact version

* Make Babel config more verbose and simpler

* Support async/await

* Enable generators

* Opt out of using helpers

Fixes #31

* Use a custom eslint rule list

* Sort rules

* Relax some rules