* [npm] upgrade babel
The upgrade to babel 6 requires an upgrade to all of the associated modules, which meant that a few other things changed at the same time. The most notable is the way that we handle our babel-options, which is now done with an npm module and includes using the babel-loader's "presets" query string param.
This meant changes to the babel_options.js module and extending it to help setting up the "babel-register" module, which was previously copy-pasted in several places.
* [mtodules] upgrade to support babel6 module semantics
* [eslint] fix lint errors
* [babel] ignoer massive fixture files
* [cli/errors] use Object.setPrototypeOf since subclassing Error is broken
* [babel] Upgrading core babel libraries
[babel] Use WIP babel-6-fix branch of babel-preset-kibana
* Fix broken test
* [babel] Reverse unnecessary module.exports changes
* Fix notifier
* Use babel presets and plugins directly
* [babel/options] resolve preset/plugins paths for better plugin compatibility
* [babel/options] use babel-preset-env for correct node settings
* [babel] cache babel compilation in webpack like we thought we were
with https://github.com/elastic/kibana/pull/5553 we added command line flags the told mocha it was supposed to use babel. This changes the strategy here and instead uses mocha's -r option (and it's mocha.opts file to specify it). This means that using mocha directly from the command line still works, and that we have a place where we can do other setup work.
