ENH: Add TractographyTRX Python wrappers

[mattcieslak]

PR Checklist

• No API changes were made (or the changes have been approved)
• No major design changes were made (or the changes have been approved)
• Added test (or behavior not changed)
• Updated API documentation (or API not changed)
• Added license to new files (if any)
• Added Python wrapping to new files (if any) as described in ITK Software Guide Section 9.5
• Added ITK examples for all new major features (if any)

Refer to the ITK Software Guide for
further development details if necessary.

This PR updates the TractographyTRX remote module to have python wrappers.
It also changes the Eigen config so that the remote module can be built as part of the ANTs superbuild.

[dzenanz]

WRAPPER_SUBMODULE_ORDER should only be set if the order of wrapping matters, e.g. one class's wrapping depends on the other. Otherwise you don't need to list them, itk_auto_load_and_end_wrap_submodules() will automatically pick up all the .wrap files. I think that if you don't manually order them, the build system has the opportunity to process them in parallel. But this is an optimization, this PR is good as-is. It builds and passes unit tests locally for me.

[mattcieslak]

Thanks! I added the ordering as a trick to get it to compile, there was an issue having CompositeTransform/AffineTransform type as an argument for TransformInPlace.

[blowekamp]

And update and refactor to ITK's Eigen was merged on Friday after noon: #5831

What this update built to work with that? The update should simplify usage of Eigen3 from ITK.

I'd recommend linking against "ITK::ITKEigen3Module" in your remote module, and library. This way the using the ITK package will provide the interface requirements and remove the need to additional find_packages for the Eigen library.

[dzenanz]

I started building local ITK with latest version to test this updated remote.

[dzenanz]

The build fails with the current main:

CMake Error at C:/Misc/ITKTractographyTRX-vs22/_deps/trx_cpp-src/CMakeLists.txt:121 (TARGET_LINK_LIBRARIES):
  Target "trx" links to:

    Eigen3::Eigen

  but the target was not found.  Possible reasons include:

    * There is a typo in the target name.
    * A find_package call is missing for an IMPORTED target.
    * An ALIAS target is missing.