Improve CONTRIBUTING file

Change-Id: Ica361186277012aed0d2910a24c81b2d01076ed7
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index a830aaf..9dd4446 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -17,10 +17,10 @@
 

 The Paho C client is stored in a git repository. The URLs to access it are:

 

-ssh://<username>@git.eclipse.org:29418/paho/org.eclipse.paho.mqtt.c

-https://<username>@git.eclipse.org/r/paho/org.eclipse.paho.mqtt.c

+- ssh://<username>@git.eclipse.org:29418/paho/org.eclipse.paho.mqtt-sn.apps

+- https://<username>@git.eclipse.org/r/paho/org.eclipse.paho.mqtt-sn.apps

 

-A [web browsable repository](http://git.eclipse.org/c/paho/org.eclipse.paho.mqtt.c.git) is available.

+A [web browsable repository](http://git.eclipse.org/c/paho/org.eclipse.paho.mqtt-sn.apps.git) is available.

 

 Contributing a patch

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