refs #100258  Merge remote branch 'origin/100258-ccndc-locate-keystore'
refs #100258  Merge remote branch 'origin/100258-ccndc-locate-keystore'

* origin/100258-ccndc-locate-keystore:
  Correct misleading error message after substituting service location for ping.  Refs# 100258
  Switch from using ping URI to localhost service locator URI to get ccndid.  Refs #100258
  Modify ccndc to use ccn_sign_content which honors CCNX_DIR rather than manipulating keystore and encoding the content object explicitly.  Refs #100258

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