base frame timestamp off epicsTS

[jsouter]

Part of a series of PRs for AreaDetector repos that sets the outgoing frames' timeStamp member to be equal to the frame's epicsTS member, updated with updateTimeStamp, when not retreiving a timestamp from hardware.

[MarkRivers]

I think I have a better solution to this problem. I have added a new method in ADCore

asynNDArrayDriver::updateTimeStamps(NDArray *pArray)

https://github.com/areaDetector/ADCore/blob/d1772ed932f958c985953f8b4c44d580585066e9/ADApp/ADSrc/asynNDArrayDriver.h#L159

This will update both timestamps, simplifying the drivers.

I have switched to this method in ADSimDetector and ADPilatus and pushed to Github.

[MarkRivers]

Note that drivers that set NDArray.timeStamp from the camera info need to call the new method before they set the camera-derived timeStamp. Otherwise it will be overwritten by the new method.