* the memory leak is inside one pass.

Update cluster_train.md for easier understanding

* some tiny fixs

* use VLOG(3)

* make AVX_FOUND is default value to WITH AVX
* let AVX_FLAG always keep -mavx flag since compiler can build binary with -mavx even CPU does not support avx.

* Init

* Add numpy deps

* Refine

* Use `gshuf` instead of `shuf` in macOS
* Fix #388

Currently, Paddle on Mac OS X is not deliberate testing through the different versions of  Mac OS X and Clang.
When all these things that we've done, we will reopen Mac build docs.

* Fix SRL hang when exit.

* Error occurred when enable Async Load in TestDataProvider.
  * It because DataProvider is calling getNextBatchInternal in one thread, and destructing DataProvider in other thread.
  * Add wait routine in DataProvider destructing.
* Also fix another bug, when destructing TestDataProvider and do not read any test data.

Fix #286

* Follow comments, Use mutex is cool!

Fix #342

* add rdma cmake support

* move rdma related code to rdma.cmake

* Add elementwise math operations
This allows use to use expressions like: y=log(1+exp(x))
Also added unittests for ActivationFunction
* Enforce keyword arguments for non-positional arguments
* Add LogActivation to doc

* Add issue template

* Update ISSUE_TEMPLATE.md

* Update ISSUE_TEMPLATE.md

* Rename

* Rename

* Typo

* Typo

* Typo

* Typo

* Follow comments

* Follow comments

* Fix glog check type unmatch in Util.cpp

#352 

For multiple installation of paddle, there might be multiple versions of python package at opt/paddle/share/wheels/. We should install the right version.
Ideally, we should remove the wrong versions when install. But it's not easy to do this with cmake.

Change-Id: Ida8a8d60643ad9e42cf1c85776de9122d5ba1392