[Dune] contains method of mapper

[Christian Engwer]

Dear all,

I just stumbled upon the contains method. We deprecateded the map<cc>
method and introduced map(...,cc). The same must be done for
contains. We have to keep the old contains<cc> method with the old
numbering and introduce a new method contains(...,cc,result).

I'll take care of this, but be warned, you might get some warnings
after your next update.

Christian