Should code under examples be ignored on eslinting
I am Johnson , a react fan and web developer.

**Proposal/Feature-request:**
examples code should be lint as well,  if a designer need help, some editor-based plugins could help make eslint pass, and Some contributors could also review and improve the code quality.

**Expected behavior:**
All JS code well lint and looks styled well. 

I can provide a pr, make the examples not ignored and exist examples be well lint.

also mentioned on [#58](https://github.com/airbnb/react-sketchapp/issues/58)
