use esprima-fb instead esprima harmony github branch

It's hard to npm install from github url in China,
CHANGES 1.1
1.1.0
Merge branch 'fengmk2-esprima-harmony'

* fengmk2-esprima-harmony:
  1.1.0
  CHANGES 1.1
  use esprima-fb instead esprima harmony github branch