remove top_k argument in classification_cost

try to fix unit test test_ProtoServer, test_TrainerOnePass

fix error: /paddle/paddle/.common_test_util.sh: line 97: netstat: command not found

Remove the requires of opencv-python.

Remove DYNAMIC_ARCH when building openblas for non-x86 target archiectures.

Merge branch 'release/0.10.0' into develop

ctest output on failure

Add flowers dataset for image classification model

Correctly handle print_layer in V2 API

rename CMAKE_CURRENT_LIST_DIR to CMAKE_CURRENT_SOURCE_DIR

update contribute_to_paddle_en.md

images reader: read the data without untarring the tarball file.
image.py: move batch function from reader to image.py

remove duplicated examples, and rename demo to v1_api_demo

Centralize the use of simd intrinsic and implement scalar kernels.

Add doc to the usage of warp-ctc.

Add a Variational Autoencoder (VAE) demo written in V1 API.

print_layer is used to print the values of a layer when evaluating the model for debugging purpose. No layer depends on print_layer. It should be added to the topology if it is used to print some layer already in the topology.

Add GLOBAL option for external library targets

move recordio to github.com/PaddlePaddle/recordio

So that they can be found when paddle is built as a add_subdirectory project in another project.

update docker version