more rigorous document
more rigorous document

* Create README-zh.rst

* Update README.rst

* Update README.rst

* Update README.rst

* Update README.rst

* Update custom_bgpd.py

* Update route_injector

* Update cmd.py

* Update default_handler.py

* Update cmd.py

* Update custom_bgpd.py

* Update route_injector

* origin

* enhance extended community support

* enhance extended community support

* remove print row

* extended community support improvement

* add document of extended community

* enhance sr-policy support for compatiblity of old and new version of iox

* sr-te support enhancement

* sr-te doc supplement

* unittest for tunnelencaps

* fix ci error

* update postman document of sr policy

* doc update

* more rigorous document

meidli/yabgp,smartbgp/yabgp,meidli/yabgp,smartbgp/yabgp