Update to clang-format-5 and reformat the codebase 

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Merge done to enable documentation be be fixed, because of removal of
alias directive and addition of related algorithms directive.

Signed-off-by: Karl Palmen <karl.palmen@stfc.ac.uk>

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Elliot Oram authored 7 years ago and Gigg, Martyn Anthony committed 7 years ago

PredictFractionalPeaks was using a new raytracer for every peak it created and therefore throwing away the caching information about the bounding boxs of detectors / panels causing a huge slow down. Resolved by exposing the findDetector(raytracer) overload to IPeaks and using single raytracer for all calls.
Work also include small refactor for const autos

Refs #22060

This option will not optimise the UB if the parameters are fixed. This
also swaps how optimisation is performed