Added determining current tenant tip.

docs/en/Multi-Tenancy.md

@@ -307,6 +307,8 @@ Volo.Abp.AspNetCore.MultiTenancy package adds following tenant resolvers to dete
 * **HeaderTenantResolver**: Tries to find current tenant id from HTTP header. Header name is "__tenant" by default.
 * **CookieTenantResolver**: Tries to find current tenant id from cookie values. Cookie name is "__tenant" by default.
 
+> If you use nginx as a reverse proxy server, please note that if `TenantKey` contains an underscore, there may be a problem, please refer to: http://nginx.org/en/docs/http/ngx_http_core_module.html#underscores_in_headers
+
 "__tenant" parameter name can be changed using AspNetCoreMultiTenancyOptions. Example:
 
 ````C#

docs/zh-Hans/Multi-Tenancy.md

@@ -308,6 +308,8 @@ Volo.Abp.AspNetCore.MultiTenancy 添加了下面这些租户解析器,从当前W
 * **HeaderTenantResolver**: 尝试从HTTP header中获取当前租户,默认的header名称是"__tenant".
 * **CookieTenantResolver**: 尝试从当前cookie中获取当前租户.默认的Cookie名称是"__tenant".
 
+> 如果你使用nginx作为反向代理服务器,请注意如果`TenantKey`包含下划线可能存在问题, 请参考: http://nginx.org/en/docs/http/ngx_http_core_module.html#underscores_in_headers
+
 可以使用AspNetCoreMultiTenancyOptions修改默认的参数名"__tenant".例如:
 
 ````C#