ENH: improve setup for paraview
- removed reliance on ParaView_INCLUDE_DIR variable for conveying the major.minor version information when compiling. This can be somewhat fragile and also adds variable that is an unnecessary when running (only used when compiling). Instead use `have_pvplugin_support` function in paraviewFunctions wmake script to determine the maj.min from the PV_PLUGIN_PATH since we have already defined the output path there with paraview maj.min numbering. Can now build with paraview from the operating system, provided that it has develop headers available. ParaView_VERSION=system In the etc/config.sh/paraview setup, the maj.min is taken from the corresponding `paraview --version` output and used when defining the PV_PLUGIN_PATH. During the build, the include path taken from `paraview-config` for a system installation, from the guess installation root of the paraview binary, or ParaView_DIR otherwise. NB: using a system ParaView for building runTimePostProcessing is unsupported. - these types of builds appear to have various library resolution issues (eg, libexpat not being loaded). Additionally, the build logic does not yet cover this type of use case.