tuto: changed preset

doc/tutorial/tutorial-clones.tex

@@ -182,7 +182,7 @@ insertions.
 
 Then you can continue aligning and clustering clones if necessary.
 
-\question{You can also try the preset \com{clone consensus length/GC content}
+\question{You can also try the preset \com{clone average read length/GC content}
   which tends to separate quite nicely the distinct clones.}
 
 Note that you can choose any axis to be plotted: just go the \com{plot} menu and