Added MatrixBase::Unit*() static function to easily create unit/basis vectors.
Removed EulerAngles, addes typdefs for Quaternion and AngleAxis,
and added automatic conversions from Quaternion/AngleAxis to Matrix3 such that:
 Matrix3f m = AngleAxisf(0.2,Vector3f::UnitX) * AngleAxisf(0.2,Vector3f::UnitY);
just works.
diff --git a/test/array.cpp b/test/array.cpp
index 6233aae..3acb4ab 100644
--- a/test/array.cpp
+++ b/test/array.cpp
@@ -53,6 +53,11 @@
   m3 = m1;
   m3.cwise() -= s1;
   VERIFY_IS_APPROX(m3, m1.cwise() - s1);
+
+  VERIFY_IS_APPROX(m1.colwise().sum().sum(), m1.sum());
+  VERIFY_IS_APPROX(m1.rowwise().sum().sum(), m1.sum());
+  VERIFY_IS_NOT_APPROX((m1.rowwise().sum()*2).sum(), m1.sum());
+  VERIFY_IS_APPROX(m1.colwise().sum(), m1.colwise().redux(ei_scalar_sum_op<Scalar>()));
 }
 
 template<typename MatrixType> void comparisons(const MatrixType& m)