[PATCH... kind of] documentation: Conditional application of limit_conn directive

[turchanov at farpost.com]

Hello!

Couldn't find (https://nginx.org/ru/docs/contributing_changes.html) 
information on
were to commit changes to documentation describing "limit_conn". I will 
post them here.
Sorry about that. (Or point me to the resource were it is explained how 
to make changes to
documentation).

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Syntax:	limit_conn zone number [if=condition];
Default:	—
Context:	http, server, location

...

The "if" parameter controls conditional application of the limit.
The limit will not be applied if the condition evaluates to "0" or an 
empty string.


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