* Update index_en.rst

* Update index_en.rst

Update  refer to commits

* Add some contents

* Adjust the content of the English version

* Fix some error, replace word generate with build

* Replace document with documentation

* Adjust contents

* Make links more visible

repair hyperlink format

fix space and toctree format

Done

fix https://github.com/PaddlePaddle/Paddle/issues/8921

fix #8956

1. add 1 sentence that was not translated in the original version
2. repair image showing problem

* update en doc for Distributed Training

* typo fix

* add is_local paramter description

* update

* update by comment

* add write_new_layers in rst tree