Change DTAG NDNProtocolDataUnit so that the encoded empty element, viewed as a string is "NDN\202\000". Refs #1056.
Added bug fix for DTAG NDNProtocolDataUnit. Refs #1056.
Merge branch 'issue/1056-fix-DTAG-NDNProtocolDataUnit'. Refs #1056.
http://redmine.named-data.net/issues/1056