* Because it is a cuda source file, and we need to support c++ 03 in
  cuda.

* Different Type compare.
* ostream << should pass a const object.
* remove always true checks.

Encourage users to file Github issues instead of emails.

modify directory structure in source code

Update sentiment_analysis.md

Sync Release Branch => Develop

Add Paddle Usage Stats Scripts.

Fix shuf/gshuf choose bug

#487

Modified API to use FLAGS_use_gpu as useGpu default value

sentiment analysis translation (#270)

modify first level directory of english doc

Fix some install package errors.

* Mount local Paddle instead of git clone from remote.
* Use official chinese ubuntu source instead of 163 mirror.

Bumping up version number to v0.9.0a0

add layer check for recurrent_group

fix bug for issue 345

Fix forwardTest for ids in python swig.

* unittest need to be added. But fix the bugs first.

Feature/pre commit hooks scripts

Add ScalingProjection