adjust the python script

* add is_test to pooling and activations

add prop_kind support for layers activation. conv and pooling

add a pass that sets is_test to true

add transpiler version of is_test pass

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* patch test and pass

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* add pass to analyzer.h

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* add is_test attr description & pass only on mkldnn

in:
activation_op.cc
batch_norm_op.cc
conv_op.cc
dropout_op.cc
lrn_op.cc
pool_op.cc
sequence_pool_op.cc
softmax_op.cc

* fix is_test handling for activation pool and conv

* change description of is_test for all layers again

* remove GetAttr(use_mkldnn) from pass

* rename correct_mkldnn_test_phase to is_test

and remove dependency on MKLDNN
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* review fix magic number

* two if(..)s into one

* Check is_test once and pass mkldnn forward prop kind

* dereference shared_ptr with * (without get())

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* add is_test_pass back

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* add selu

* use for range
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* add API
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* follow comment
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* update API.spec
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* fix test_save_load with pickle

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* fix test_save_load with pickle

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* fix test_save_load with pickle

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* Support softmax return in softmax_with_cross_entropy

* Add test for return_softmax=False

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Density prior box operator for image detection model.

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* add lod tensor array concat

* add lod tensor array concat

* test=develop

* add lod tensor array concat
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* Fix API.spec
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* add lod tensor array concat
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* revise some bug of lod tensor array concat
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* add unittest for tensor array concat
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* change to tensor array to tensor
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* revise bug
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* revise a bug
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* revise a bug
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* revise a bug of python3
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* exhaustive search for cuDNN conv.
* Refine code and add unit testing.
* Fix model load in fluid/inference and unit testing in conv2d
* Follow comments.
* Fix compiling test=develop

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the build strategy is finalized after create_passes. So future
change of build strategy has no effects.

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