Final fixes for Memory_used

- Change some static variables to dynamic to ensure that we don't do any memory
  allocations before server starts or stops
- Print more memory information on SIGHUP. Fixed output.
- Write out if memory was lost if run with --debug-at-exit
- Fixed wrong #ifdef in sql_cache.cc

sql/sql_repl.cc

@@ -182,6 +182,7 @@ struct binlog_send_info {
   {
     error_text[0] = 0;
     bzero(&error_gtid, sizeof(error_gtid));
+    until_binlog_state.init();
   }
 };