Implement extended dispersion spotfinding

[dimitrivlachos]

Implement the extended dispersion spotfinding algorithm. This improves the accuracy of the spotfinder by using a first-pass to mask out the potential signal areas from the background calculation before performing a second pass for true signal identification.

[graeme-winter]

Just a note on the implementation here - we would probably like to be able to switch at run time between kernels e.g. mode=dispersion / mode=extended or similar

[dimitrivlachos]

Just a note on the implementation here - we would probably like to be able to switch at run time between kernels e.g. mode=dispersion / mode=extended or similar

I did add the kernel selection as an argument, so it is selectable at run time 😄

Is this implementation acceptable @graeme-winter?

[graeme-winter]

Just a note on the implementation here - we would probably like to be able to switch at run time between kernels e.g. mode=dispersion / mode=extended or similar

I did add the kernel selection as an argument, so it is selectable at run time 😄

Is this implementation acceptable @graeme-winter?

Didn't mean to imply it wasn't there, just thought I would look later but this thought was in my head now ;-) so happy it was preempted