Merge remote-tracking branch 'origin/feature/6768_live_data_cancellation'
Merge remote-tracking branch 'origin/feature/6718_FasterLoadIsawPeaks'
Refs #6779 Use shared_ptr as Python HeldType for PythonAlgorithms

This allows us to release Python from managing the memory when the
algorithms are created via the instantiator from the factory. It also
keeps Python managing the object references correctly when created
purely from Python.
Merge branch 'feature/6779_python_algs_memleak' into develop