Configuration: remove raw pointers from interfaces

[obiltschnig]

Similar to Logging.

[aleks-f]

same as here, although more severe - there were duplicate add calls (non-shared and shared version), so adding AutoPtr overloads on top of that seemed like too much; I'm not quite sure why those overloads existed and I'm thinking everything should be shared, simpler and cleaner. If we decide that we really, really want to keep the pointer versions, then those can be reinstated, but I think internally (for Logging and Configuration) things should only be kept as AutoPtr

Note: valgrind reports tons of leaks from the new PropertyListConfiguration, I guess those should be resolved when this issue is taken care of /cc @DraconPern

[DraconPern]

Tracking. Let me see if I can fix the memory leaks.

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This issue is stale because it has been open for 365 days with no activity.

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This issue was closed because it has been inactive for 60 days since being marked as stale.