coffeescript 2, rails, sprockets, and execjs

[Pirate Praveen <praveen@onenetbeyond.org>]

Hi,

Recent major update of coffeescript broke rails build and now I'm stuck 
with https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1013218

coffeescript 2 produces ES6 by default but execjs don't support ES6 yet.

I tried with newer sprockets, but it seems not enough. In the short 
term, may be using babel to transpile to ES5 is the way forward.

Any help with fixing this is welcome.

Thanks
Praveen