Feature: add a PDAL plugin

[gapry]

Related Issue:

This work addresses the Issue: #201

How To Test the Plugin

rm -rf build
mkdir build
cd build
cmake -GNinja -DCMAKE_PREFIX_PATH="../vtk/install" -DF3D_MODULE_UI=OFF -DF3D_PLUGIN_BUILD_PDAL=ON ../src
ninja

Current Issue:

1. Can not find the VTK::IOPDAL package
   According to the VTK document, https://docs.vtk.org/en/latest/modules/index.html, I know I need to use VTK::IOPDAL so I define it in the DEPENDS section in the vtk.module, but still can not compile, it occurs the following error. Any idea to help? Thanks

   Could not find the VTK package with the following required components:
   IOPDAL.
   

2. EXTENSIONS and MIMETYPES
   I refer to the USD Plugin CMakeLists.txt to write the PDAL Plugin CMakeLists.txt

   (a) I want to confirm if the EXTENSIONS bpf matlab npy pgpointcloud tiledb as listed in the PDAL Reader document, are considered plugin goals?

   (b) According to the USD Plugin CMakeLists.txt, I need to locate files whose types are defined in the MIMETYPES for each category (e.g. application, model). Should all these files comply with the Creative Commons license? If yes, which types are required? https://creativecommons.org/share-your-work/cclicenses/

[mwestphal]

Could not find the VTK package with the following required components: IOPDAL.

Did you modify your build of VTK ? This module is not enabled by default in VTK.