explicit that CSR, BCSR, COO are sparse matrices

contents/index.html

@@ -187,7 +187,7 @@ automatically determine which version is best for each input size (new in v0.9).
 <h4>Genericity</h4>
   <p>
 The StarPU programming interface is very generic. For intance, various data
-structures are supported mainline (vectors, dense matrices, CSR matrices, ...),
+structures are supported mainline (vectors, dense matrices, CSR/BCSR/COO sparse matrices, ...),
 but application-specific data structures can also be supported, provided that
 the application describes how data is to be transfered (e.g. a series of
 contiguous blocks). That was for instance used for hierarchically-compressed