check-code: catch "echo -n" in tests stable

check-code: catch "echo -n" in tests

--- a/contrib/check-code.py	Thu Aug 12 20:54:34 2010 -0300
+++ b/contrib/check-code.py	Sun Aug 15 17:48:05 2010 +0200
@@ -46,6 +46,7 @@
     (r'^function', "don't use 'function', use old style"),
     (r'grep.*-q', "don't use 'grep -q', redirect to /dev/null"),
     (r'echo.*\\n', "don't use 'echo \\n', use printf"),
+    (r'echo -n', "don't use 'echo -n', use printf"),
     (r'^diff.*-\w*N', "don't use 'diff -N'"),
     (r'(^| )wc[^|]*$', "filter wc output"),
     (r'head -c', "don't use 'head -c', use 'dd'"),