* support rectangle padding, stride, window and input for PoolProjection

* Follow comments.
1. Remove start
2. refine img_pool_a/b.conf for test_NetworkCompare
3. Split unit test

* Modify the test in img_layers.py

* add interface and unittest of RecurrentGradientMachine for the function of multiple Subsequence inlinks with unequal token length

* refine sparse momentum api and unittest
* fix unittests bug

* Fix lots of trainer_config_helpers bug, and complete unittest for `layers.py`

* Correctly handling multiple inputs and integer inputs for recurrent_group

* Fix ScatterAgentLayer for generation

* Revert sequence_(nest)_rnn.conf

* Add `device` parameter to ExtraAttr in trainer_config_helpers.
* add unittest for it.

* add type compatible check for ParamAttr

* fix bug in dotmul_operator's api and anotation
* update rnn document
* remove redundant info of projection and operator in layers.py

* remove unnecessary field set in ParameterConfig, Evaluators, etc

* split dotmul_projection and dotmul_operator
* bug fix in outputsize checking for mixed layer

Sequences should be sorted according to the number of subsequences they have.

Sequences should be sorted according to the number of subsequences they have.

* Add some comments for CTC layer and fix CTC evalutors, also add interface test

Change cos_sim to use CosSimLayer layer when size=1 and rename convex_comb_layer to linear_comb_layer

Also add an unittest for layers.py, currently for a few things. More need to be added later.

Change-Id: Id0804d03fc15529a8cf0b13c9e97d628103f5cec

Change-Id: Ia5358f88129b5c2e2a2653b1d85c168b80d797b3

* Fix ParameterAttribute for img_conv_layer, tensor_layer, crf_layer, crf_decoding_layer.

Change-Id: Ic24e4bc1f9d5e03bf35058b49a54c78caf7e97a8

ISSUE=4619881 

git-svn-id: https://svn.baidu.com/idl/trunk/paddle@1502 1ad973e4-5ce8-4261-8a94-b56d1f490c56

ISSUE=4612671

git-svn-id: https://svn.baidu.com/idl/trunk/paddle@1501 1ad973e4-5ce8-4261-8a94-b56d1f490c56

ISSUE=4612433 

git-svn-id: https://svn.baidu.com/idl/trunk/paddle@1476 1ad973e4-5ce8-4261-8a94-b56d1f490c56

ISSUE=4611081


git-svn-id: https://svn.baidu.com/idl/trunk/paddle@1475 1ad973e4-5ce8-4261-8a94-b56d1f490c56

Also fix link in quick_start

ISSUE=4611783



git-svn-id: https://svn.baidu.com/idl/trunk/paddle@1474 1ad973e4-5ce8-4261-8a94-b56d1f490c56

ISSUE=4611579

git-svn-id: https://svn.baidu.com/idl/trunk/paddle@1473 1ad973e4-5ce8-4261-8a94-b56d1f490c56

ISSUE=4599577


git-svn-id: https://svn.baidu.com/idl/trunk/paddle@1440 1ad973e4-5ce8-4261-8a94-b56d1f490c56

ISSUE=4592807 

git-svn-id: https://svn.baidu.com/idl/trunk/paddle@1423 1ad973e4-5ce8-4261-8a94-b56d1f490c56

ISSUE=4539687

git-svn-id: https://svn.baidu.com/idl/trunk/paddle@1422 1ad973e4-5ce8-4261-8a94-b56d1f490c56

ISSUE=4584581 

git-svn-id: https://svn.baidu.com/idl/trunk/paddle@1413 1ad973e4-5ce8-4261-8a94-b56d1f490c56

Also add some comments for cost layers.
ISSUE=4580653

git-svn-id: https://svn.baidu.com/idl/trunk/paddle@1410 1ad973e4-5ce8-4261-8a94-b56d1f490c56

ISSUE=4586495

git-svn-id: https://svn.baidu.com/idl/trunk/paddle@1408 1ad973e4-5ce8-4261-8a94-b56d1f490c56