modify nginx-1.11.10 to nginx 1.16.1 in tutorial.

Update F-Stack_Nginx_APP_Guide.md

The context of `schedule_timeout` is `main`.

Update F-Stack_Nginx_APP_Guide.md

The context of `schedule_timeout` is `main`.

Update F-Stack_Nginx_APP_Guide.md

Update F-Stack_Nginx_APP_Guide.md

Nginx : directive proxy_kernel_network_stack
1. Add a new directive proxy_kernel_network_stack :
Syntax: proxy_kernel_network_stack on | off;
Default: proxy_kernel_network_stack off;
Co

Nginx : directive proxy_kernel_network_stack
1. Add a new directive proxy_kernel_network_stack :
Syntax: proxy_kernel_network_stack on | off;
Default: proxy_kernel_network_stack off;
Context: http, stream, mail, server
This directive is available only when NGX_HAVE_FF_STACK is defined.
Determines whether proxy should go throught kernel network stack or fstack.
2.Update F-Stack_Nginx_APP_Guide.md

show more ...

Nginx : directive proxy_kernel_network_stack
1. Add a new directive proxy_kernel_network_stack :
Syntax: proxy_kernel_network_stack on | off;
Default: proxy_kernel_network_stack off;
Co

Nginx : directive proxy_kernel_network_stack
1. Add a new directive proxy_kernel_network_stack :
Syntax: proxy_kernel_network_stack on | off;
Default: proxy_kernel_network_stack off;
Context: http, stream, mail, server
This directive is available only when NGX_HAVE_FF_STACK is defined.
Determines whether proxy should go throught kernel network stack or fstack.
2.Update F-Stack_Nginx_APP_Guide.md

show more ...

Update F-Stack_Nginx_APP_Guide.md

Add description of directive ```kernel_network_stack```.

Update F-Stack_Nginx_APP_Guide.md

Add description of directive ```kernel_network_stack```.

Update F-Stack_Nginx_APP_Guide.md

Handle fstack in nginx ```work process cycle```. Refer to #151.

Update F-Stack_Nginx_APP_Guide.md

Handle fstack in nginx ```work process cycle```. Refer to #151.

Fix nginx coredump on virtio vm and support kni.

1.close #67.
2.replace ff_primary process to primary worker process(the first one to
start and the last one to exit).
3.it's not graceful to reload.

Update nginx doc

Update nginx doc

Update doc/F-Stack_Nginx_APP_Guide.md

Support nginx reload.

close #12.
For more details, see doc/F-Stack_Nginx_APP_Guide.md.

init