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

* modify RecurrentGradientMachine to support hasSubSeq sequence inlinks with the same number of sentence but different number of tokens for each sentence

Change-Id: Ic71f00a4bb346b4fa93e650dfb4b1a0d8d2338b0

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.

* fix CUDNN_VERSION for backward of CudnnBatchNormLayer

* fix cudnn version number for BatchNorm

* the last layer in the stack already has all the suffixes

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