Fix compilation with latest ndn-cxx

And switch source archive to xz compression

Change-Id: I2d6cf9c0f455dd377308b51f80997e4731d11fa2
diff --git a/wscript b/wscript
index 5aa05c9..435fbd0 100644
--- a/wscript
+++ b/wscript
@@ -197,7 +197,9 @@
         Logs.warn('%s is not writable (%s)' % (versionFile, e.strerror))
 
 def dist(ctx):
+    ctx.algo = 'tar.xz'
     version(ctx)
 
 def distcheck(ctx):
+    ctx.algo = 'tar.xz'
     version(ctx)