- corrected licenses for the stuff that was by the TuxKart team

git-svn-id: svn+ssh://svn.code.sf.net/p/supertuxkart/code/trunk/supertuxkart@1535 178a84e3-b1eb-0310-8ba1-8eac791a3b58

data/licenses

@@ -20,7 +20,7 @@ tk7.ogg,
 tuxr.ogg,
 Boom_boom_boom.ogg
 ------------------
-  Matt Thomas, license: CC
+  Matt Thomas, license: GNU GPL v2 (or later)
 
 main_theme.ogg,
 kart_grand_prix.ogg
@@ -50,5 +50,5 @@ New shifting sand and lighthouse textures
 
 All other textures
 ------------------
-  Steve Baker, license: CC
-  
+  Steve Baker, license: GNU GPL v2 (or later)
+