Merge pull request #8658 from luotao1/doc_en

adjust the structure of documentation (en)

doc/build_and_install/pip_install_en.rst

-Install Using pip
+Install using pip
 ================================
 
 You can use current widely used Python package management
@@ -8,7 +8,7 @@ most of current Linux systems or MacOS.
 
 .. _pip_install:
 
-Install Using pip
+Install using pip
 ------------------------------
 
 Run the following command to install PaddlePaddle on the current

doc/dev/index_en.rst

@@ -4,6 +4,5 @@ Development
 ..  toctree::
   :maxdepth: 1
 
-  new_layer_en.rst
   contribute_to_paddle_en.md
   write_docs_en.rst

doc/faq/build_and_install/index_en.rst

+############################
+Install, Build and Unit test
+############################
+
+TBD

doc/faq/cluster/index_en.rst

+###############################
+Cluster Training and Prediction
+###############################
+
+TBD

doc/faq/index_en.rst

+FAQ
+====
+
+ 
+..  toctree::
+  :maxdepth: 1
+
+  build_and_install/index_en.rst
+  model/index_en.rst
+  parameter/index_en.rst
+  local/index_en.rst
+  cluster/index_en.rst

doc/faq/local/index_en.rst

+#############################
+Local Training and Prediction
+#############################
+
+TBD

doc/faq/model/index_en.rst

+###################
+Model Configuration
+###################
+
+TBD

doc/faq/parameter/index_en.rst

+#################
+Parameter Setting
+#################
+
+TBD

doc/getstarted/concepts/use_concepts_en.rst

+Basic Concept
+=============
+TBD

doc/getstarted/index_en.rst

@@ -5,3 +5,4 @@ GET STARTED
   :maxdepth: 1
 
   quickstart_en.rst
+  concepts/use_concepts_en.rst

doc/howto/capi/compile_paddle_lib_en.md

+## Install and Build
+
+TBD

doc/howto/capi/index_en.rst

+C-API Prediction Library
+========================
+
+..  toctree::
+  :maxdepth: 1
+
+  compile_paddle_lib_en.md
+  organization_of_the_inputs_en.md
+  workflow_of_capi_en.md

doc/howto/capi/organization_of_the_inputs_en.md

+## Input/Output Data Organization
+
+TBD

doc/howto/capi/workflow_of_capi_en.md

+## C-API Workflow
+
+TBD

doc/howto/cluster/multi_cluster/fabric_en.md

-# Cluster Training Using Fabric
+# Fabric
 
 ## Prepare a Linux cluster
 

doc/howto/cluster/multi_cluster/k8s_aws_en.md

-
-# Distributed PaddlePaddle Training on AWS with Kubernetes
+# Kubernetes on AWS
 
 We will show you step by step on how to run distributed PaddlePaddle training on AWS cluster with Kubernetes. Let's start from core concepts.
 

doc/howto/cluster/multi_cluster/k8s_distributed_en.md

+# Kubernetes Distributed
+
+TBD

doc/howto/cluster/multi_cluster/k8s_en.md

-# PaddlePaddle On Kubernetes
+# Kubernetes
 
 In this article, we will introduce how to run PaddlePaddle training job on single CPU machine using Kubernetes. In next article, we will introduce how to run PaddlePaddle training job on distributed cluster.
 

doc/howto/cluster/multi_cluster/openmpi_cn.md

-# 在OpenMPI集群中提交训练作业
+# 在OpenMPI集群中启动训练
 
 ## 准备OpenMPI集群
 

doc/howto/cluster/multi_cluster/openmpi_en.md

-# Cluster Training Using OpenMPI
+# OpenMPI
 
 ## Prepare an OpenMPI cluster
 

doc/howto/rnn/hierarchical_layer_en.rst

+Layers supporting hierarchical sequence as input
+================================================
+
+TBD

doc/howto/rnn/hrnn_rnn_api_compare_en.rst

+API comparision between RNN and hierarchical RNN
+================================================
+
+TBD

doc/howto/rnn/index_en.rst

@@ -5,3 +5,6 @@ RNN Models
   :maxdepth: 1
 
   rnn_config_en.rst
+  recurrent_group_en.md
+  hierarchical_layer_en.rst
+  hrnn_rnn_api_compare_en.rst

doc/howto/rnn/recurrent_group_en.md

+# Recurrent Group Tutorial
+
+TBD

doc/index_en.rst

@@ -8,3 +8,4 @@ PaddlePaddle Documentation
   build_and_install/index_en.rst
   howto/index_en.rst
   dev/index_en.rst
+  faq/index_en.rst