ndnmap-data-collector: Update to build using ndn-cxx 0.7.0

Change-Id: I5c3138cc6efacf1569cb95c697790aafbaf5d753
diff --git a/ndnmap-data-collector/Makefile b/ndnmap-data-collector/Makefile
index c1420df..50ccb6f 100644
--- a/ndnmap-data-collector/Makefile
+++ b/ndnmap-data-collector/Makefile
@@ -11,6 +11,6 @@
 VERSION=0.1.0-15-g29c1984
 
 # PPA version
-PPA_VERSION=2
+PPA_VERSION=4
 
 include ../packaging.mk