ccnd: Squelch duplicate interests on broadcast faces better.
ccnd: Squelch duplicate interests on broadcast faces better.

See inline comments.

refs #73  Interest/Data protocol specification
refs #13  ccnd should suppress duplicate interests in all cases

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