python: Update to draft version to 7 in hpackmake.py

python/hpackmake.py

@@ -15,7 +15,7 @@ import nghttp2
 
 def testsuite(testdata, filename, outdir, table_size, deflate_table_size):
     res = {
-        'draft':6,
+        'draft':7,
         'description': '''\
 Encoded by nghttp2. The basic encoding strategy is described in \
 http://lists.w3.org/Archives/Public/ietf-http-wg/2013JulSep/1135.html \