Reference - finish Util RPCs

- Update last util RPC (getmemoryinfo)

_includes/devdoc/dash-core/rpcs/rpcs/getmemoryinfo.md

@@ -9,10 +9,15 @@ http://opensource.org/licenses/MIT.
 
 {% assign summary_getMemoryInfo="returns information about memory usage." %}
 
+<!-- __ -->
+
 {% autocrossref %}
 
 *Added in Bitcoin Core 0.14.0*
 
+**_Not implemented in Dash Core (as of 0.12.2)_**
+
+{% comment %}
 The `getmemoryinfo` RPC {{summary_getMemoryInfo}}
 
 *Parameters: none*
@@ -88,4 +93,6 @@ Result:
 
 * [GetMemPoolInfo][rpc getmempoolinfo]: {{summary_getMemPoolInfo}}
 
+{% endcomment %}
+
 {% endautocrossref %}