Helm cleanup

Such bindings prevent editing the *grep buffer.
Auto install thrift-mode
Clean up prelude-coffee.el
js2-mode is awesome
Add json-mode
Merge pull request #708 from toctan/coffee

Clean up prelude-coffee.el
Merge pull request #706 from toctan/thrift

Auto install thrift-mode
Merge pull request #705 from tuhdo/master

Helm cleanup
Merge pull request #707 from toctan/js2-mode

js2-mode is awesome
Merge remote-tracking branch 'bbatsov/master'

* bbatsov/master:
  Add json-mode
  js2-mode is awesome
  Clean up prelude-coffee.el
  Auto install thrift-mode
  Helm cleanup