Compatibility with recent nanoflann versions.

[jdumas]

• v1.5.0: Changed output arg from std::pair<> to nanoflann::ResultItem<>
• v1.5.0: naonflann::SearchParams renamed to naonflann::SearchParameters (because the first arg in the constructor was also removed from the API).
• v1.4.0: default template arg for IndexType/AccessorType was changed from size_t to uint32_t:
  Several fixes for IndexType which are not of integral types jlblancoc/nanoflann#154

I haven't updated the nanoflann version bundled with geometry-central, but I've confirmed that it compiles locally with the latest version.

[phaedon]

This would be great; I had to add support for a really old version of nanoflann in order to check this library into the Bazel registry:

bazelbuild/bazel-central-registry@42a43ca

[nmwsharp]

thanks for this! I went ahead and updated the included nanoflann at the same time, since it was an ancient version