build: update waf to version 2.0.27

Change-Id: Ifc91195b5d6a7f5feb63e0902d1ee2b39f1bba21
diff --git a/.jenkins.d/01-ndn-cxx.sh b/.jenkins.d/01-ndn-cxx.sh
index 6c7fb22..d89b426 100755
--- a/.jenkins.d/01-ndn-cxx.sh
+++ b/.jenkins.d/01-ndn-cxx.sh
@@ -35,7 +35,7 @@
 
 pushd ndn-cxx >/dev/null
 
-./waf --color=yes configure --without-osx-keychain
+./waf --color=yes configure
 ./waf --color=yes build
 sudo ./waf --color=yes install