merge r3454, r3455, r3486, r3496, r3519, r3523: SSI fixes: *) use content type of the parent request in SSI stub block output instead of default one *) SSI %s timefmt has no timezone offset *) change ngx_http_ssi_filter and ngx_http_charset_filter order *) do not store an encoded variable value as a new cached variable value *) fix SSI include stub for valid empty responses *) allow to use $uid_got in SSI and perl module

--- a/src/http/modules/ngx_http_userid_filter_module.c
+++ b/src/http/modules/ngx_http_userid_filter_module.c
@@ -545,7 +545,7 @@ ngx_http_userid_add_variables(ngx_conf_t
 {
     ngx_http_variable_t  *var;
 
-    var = ngx_http_add_variable(cf, &ngx_http_userid_got, NGX_HTTP_VAR_NOHASH);
+    var = ngx_http_add_variable(cf, &ngx_http_userid_got, 0);
     if (var == NULL) {
         return NGX_ERROR;
     }