Mermaid chart should report the rows, columns and time of the resultset

[joocer]

Currently, the mermaid version of the query plan doesn't display information about the result of the query, this could be done by adding a "HEAD" node:

NODE_HEAD@{ shape: sm-circ }

and an edge to this node, something like this:

NODE_xxxxxxxxxx -- 0 rows<br />0 columns<br />0 bytes<br />0ms --> NODE_HEAD