Added a remove by key function to AssocUnique
Added a remove by key function to AssocUnique

nekulin/arangodb,nvoron23/arangodb,nvoron23/arangodb,nvoron23/arangodb,nekulin/arangodb,nvoron23/arangodb,nekulin/arangodb,nekulin/arangodb,nekulin/arangodb,nvoron23/arangodb,nvoron23/arangodb,nekulin/arangodb,nvoron23/arangodb,nekulin/arangodb,nekulin/arangodb,nekulin/arangodb,nvoron23/arangodb,nvoron23/arangodb,nvoron23/arangodb,nekulin/arangodb