Manta flow used the `__main__` namespace which it was executed in, this caused a bug when calculating fluid from Python, which clears it's `__main__` name-space after execution. This caused Manta-flows name space to be cleared too. Resolve this by creating a separate name-space for manta-flow. Reviewed by: SonnyCampbell_Unity Ref D15269
When updating a library remember to: * Update the README.blender with the corresponding version. * Update the THIRD-PARTY-LICENSE.txt document