AssocVector implicit copy constructor warning

[Qix-]

Getting the following error compiling with Clang and -Werror -Wextra -Wall:

../ext/kiwi/kiwi/AssocVector.h:139:22: error: definition of implicit copy constructor for 'AssocVector<kiwi::impl::Symbol, double>' is deprecated because it has a user-declared copyassignment operator [-Werror,-Wdeprecated-copy]
        AssocVector& operator=(const AssocVector& rhs)
                     ^
../ext/kiwi/kiwi/row.h:29:5: note: in implicit copy constructor for 'Loki::AssocVector<kiwi::impl::Symbol, double>' first required here
    Row(const Row &other) = default;
    ^
../ext/kiwi/kiwi/solverimpl.h:497:23: note: in defaulted copy constructor for 'kiwi::impl::Row' first required here
                m_rows[ art ] = new Row( row );

I will probably fix this and PR at some point but just wanted to point it out in case I forget.