Fix ccnslurp to use only passive interests
Fix ccnslurp to use only passive interests

refs #272

svartika/ccnx,ebollens/ccnmp,ebollens/ccnmp,cawka/ndnx,cawka/ndnx,svartika/ccnx,svartika/ccnx,cawka/ndnx,svartika/ccnx,ebollens/ccnmp,svartika/ccnx,svartika/ccnx,cawka/ndnx,cawka/ndnx,ebollens/ccnmp,svartika/ccnx