Add the reordering buttons to the flow chart layout

[boinst]

In the flow chart layout, you don't get reorder buttons. You do get reorder buttons in the workflow diagram layout.

I suggest that the reorder buttons be exposed in both layouts.

In many flow chart diagrams, the order doesn't matter, but if there are multiple boxes at the same hierarchy level, the order does matter.

here is an example of such a diagram, where the order is meaningful.