Rename 'src' directory to 'ndn-cxx'

Change-Id: I14394023680901a86977313ca87fb017333614dd
Refs: #3084
diff --git a/.jenkins.d/30-coverage.sh b/.jenkins.d/30-coverage.sh
index 5910069..92f2bb8 100755
--- a/.jenkins.d/30-coverage.sh
+++ b/.jenkins.d/30-coverage.sh
@@ -9,7 +9,7 @@
 if [[ $JOB_NAME == *"code-coverage" ]]; then
     gcovr --object-directory=build \
           --output=build/coverage.xml \
-          --filter="$PWD/src" \
+          --filter="$PWD/ndn-cxx" \
           --root=. \
           --xml