I merged this PR earlier today, in the mistaken belief that review comments had been made, and handled fully. However grkvlt (Andrew Kennedy) was still in the process of reviewing it and had further review comments to make.
I have now reverted PR #43 so grkvlt can continue. My apologies for the inconvenience to anyone who started work off master, or rebased, during the window between the two events. But mostly an apology to grkvlt; he was reviewer for the commit and it was not appropriate for me to jump in as I did. Richard.
