use MurmurHash2 for split_clients, because
its distribution is much better than CRC32's one

src/http/modules/ngx_http_split_clients_module.c

diff --git a/src/http/modules/ngx_http_split_clients_module.c b/src/http/modules/ngx_http_split_clients_module.c
index c28b8f9..a43fac5 100644
--- a/src/http/modules/ngx_http_split_clients_module.c
+++ b/src/http/modules/ngx_http_split_clients_module.c
@@ -87,7 +87,7 @@
         return NGX_OK;
     }
 
-    hash = ngx_crc32_short(val.data, val.len);
+    hash = ngx_murmur_hash2(val.data, val.len);
 
     part = ctx->parts.elts;