Set this up to run on CI in the babylon repo?

if anyone wants to do it

```
--- v7.0.0-beta.49
Node: v8.10.0
ITERATIONS: 20
fixture babylon acorn esprima
./fixtures/backbone.js 11.8ms 5.2ms 8.8ms
./fixtures/jquery.js 56.1ms 20.8ms 37.4ms
./fixtures/babylon-dist.js 71.6ms 28.4ms 61.0ms
./fixtures/angular.js 109.8ms 63.3ms 88.3ms
./fixtures/react-with-addons.js 110.2ms 68.2ms 86.3ms
./fixtures/ember.debug.js 273.9ms 188.1ms 240.3ms

--- v7.0.0-beta.31
Node: v8.9.1
ITERATIONS: 20
fixture babylon
./fixtures/backbone.js 19.4ms
./fixtures/jquery.js 82.0ms
./fixtures/babylon-dist.js 101.5ms
./fixtures/angular.js 132.9ms
./fixtures/react-with-addons.js 137.6ms
./fixtures/ember.debug.js 332.3ms

--- v6.18.0
Node: v8.9.1
ITERATIONS: 20
fixture babylon
./fixtures/backbone.js 69.7ms
./fixtures/jquery.js 332.6ms
./fixtures/babylon-dist.js 400.0ms
./fixtures/angular.js 554.9ms
./fixtures/react-with-addons.js 478.6ms
./fixtures/ember.debug.js 951.1ms

Node: v8.9.1
ITERATIONS: 20
fixture acorn6to5v0.11.1-31 acorn v5 esprima v4
./fixtures/backbone.js 9.9ms 6.6ms 7.0ms
./fixtures/jquery.js 43.4ms 24.1ms 39.5ms
./fixtures/babylon-dist.js 62.5ms 27.9ms 65.7ms
./fixtures/angular.js 89.8ms 83.5ms 102.7ms
./fixtures/react-with-addons.js 87.4ms 88.6ms 97.3ms
./fixtures/ember.debug.js 253.8ms 232.9ms 290.8ms

Node: v8.9.1
ITERATIONS: 20
fixture acornv0.10 acorn6to5v0.9.1-16
./fixtures/backbone.js 10.8ms 5.2ms
./fixtures/jquery.js 40.2ms 18.4ms
./fixtures/babylon-dist.js 56.3ms 54.8ms
./fixtures/angular.js 82.3ms 82.5ms
./fixtures/react-with-addons.js 85.3ms 87.7ms
./fixtures/ember.debug.js 234.7ms 254.4ms
```