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Changes the ImplicitGeomeryHolder class to accept Visitors on itself
instead of deferring the call to the prototype geometry. This fixes the
occurence of some CCM errors during checking and is required for the
implementation of the planned topological checks.

fix solid self intersection incorrectly ignoring degenerated triangles depending on planarity settings

Adds the handling and creation of the embedded database in RAM, which is
used for the in-memory and fallback modes.