Method Extrema_GenExtCC::Perform() refactored to avoid very inefficient (O(N^2)) algorithm of removal of duplicate points at the end. Instead, duplications are checked when new points are added.
Fields are initialized in constructors of the class Extrema_GenExtCC; unused instances of generic classes (duplications) ELCC and ELCC2d removed.
Test case bugs/modalg_6/bug26064 added.
