big addons:

* add Homogeneous expression for vector and set of vectors (aka matrix)
  => the next step will be to overload operator*
* add homogeneous normalization (again for vector and set of vectors)
* add a Replicate expression (with uni-directional replication
  facilities)
=> for all of them I'll add examples once we agree on the API
* fix gcc-4.4 warnings
* rename reverse.cpp array_reverse.cpp

Eigen/Array

@@ -35,6 +35,7 @@ namespace Eigen {
 #include "src/Array/PartialRedux.h"
 #include "src/Array/Random.h"
 #include "src/Array/Norms.h"
+#include "src/Array/Replicate.h"
 #include "src/Array/Reverse.h"
 
 } // namespace Eigen