Add option to show retry button on c-loader-status

[ascott18]

Add an addtional c-loader-status flag that presents a button for failed requests and allows the user to retry it.

Problems to be solved:

• How is the request re-invoked? Do we capture the args of the failed call and re-call with the same args? I think we have to- hard to imagine another way.
• What happens if a single set of status flags is displaying multiple loaders? Do we display multiple buttons, or a single button that reloads all failures? I think the latter is what we have to do.