Update more OSC links

plugins/osc/README.developer.md

@@ -18,9 +18,10 @@ Before we begin you should do the following:
 * Have an understanding of the map & vector classes from the STL
   (http://www.sgi.com/tech/stl/ or http://www.cplusplus.com/reference/stl/).
 * Know something about the
-  [OSC specification](http://opensoundcontrol.org/spec-1_0). You don't need
-  to know the wire format for the OSC messages. but you should at least
-  recognize OSC addresses and know the different data types in a message.
+  [OSC specification](https://opensoundcontrol.stanford.edu/spec-1_0.html).
+  You don't need to know the wire format for the OSC messages. but you
+  should at least recognize OSC addresses and know the different data types
+  in a message.
 * Look at the [liblo site](http://liblo.sourceforge.net/) and read the
   examples.
 * Get familiar with the