terminateMantaflow was never called, this leak is more of a technicality since it's only called on exit. Also make Py_Initialize/Py_Finalize optional in Pd:setup/finalize as it caused Blender to crash, finalizing Python twice. Add a patch to extern/mantaflow to keep track of changes in Blender from up-stream.
When updating a library remember to: * Update the README.blender with the corresponding version. * Update the THIRD-PARTY-LICENSE.txt document