Cleanup SFINAE in Array/Matrix(initializer_list) ctors and minor doc editing.

doc/TutorialMatrixClass.dox

@@ -101,38 +101,39 @@ Matrix3f a(3,3);
 \endcode
 and is a no-operation.
 
-Additionally, we also offer some constructors to initialize the coefficients of small fixed-size vectors up to size 4:
+Matrices and vectors can also be initialized from lists of coefficients.
+Prior to C++11, this feature is limited to small fixed-size column or vectors up to size 4:
 \code
 Vector2d a(5.0, 6.0);
 Vector3d b(5.0, 6.0, 7.0);
 Vector4d c(5.0, 6.0, 7.0, 8.0);
 \endcode
 
-If C++11 is enabled, matrices can be constructed and initialized using initializer lists. In the case of fixed-sized vectors
-and rowvectors a simple initializer list can be passed:
+If C++11 is enabled, fixed-size column or row vectors of arbitrary size can be initialized through a single initializer list (\link Matrix::Matrix(const std::initializer_list<Scalar>&) details \endlink):
 \code
-Vector2i a {1, 2};                  // A vector containing the elements {1, 2}
-Matrix<int, 4, 1> b {1, 2, 3, 4};   // A row-vector containing the elements {1, 2, 3, 4}
-Matrix<int, 1, 4> c {1, 2, 3, 4};   // A vector containing the elements {1, 2, 3, 4}
+Vector2i a {1, 2};                     // A column vector containing the elements {1, 2}
+Matrix<int, 5, 1> b {1, 2, 3, 4, 5};   // A row-vector containing the elements {1, 2, 3, 4, 5}
+Matrix<int, 1, 5> c {1, 2, 3, 4, 5};   // A column vector containing the elements {1, 2, 3, 4, 5}
 \endcode
 
-In the case of fixed or dynamically sized matrices an initializer list containing an initializer list for each row
-can be passed. If the matrix is fixed-sized, the number of elements that are passed must match the dimensions.
+In the general case of matrices and vectors with either fixed or runtime sizes,
+coefficients have to be grouped by rows and passed as an initializer list of initializer list (\link Matrix::Matrix(const std::initializer_list<std::initializer_list<Scalar>>&) details \endlink):
 \code
-MatrixXi a {
+MatrixXi a {      // construct a 2x2 matrix
       {1, 2},     // first row
       {3, 4}      // second row
 };
 Matrix<double, 2, 3> b {
-      {2.0, 3.0, 4.0},
-      {5.0, 6.0, 7.0},
+      {2, 3, 4},
+      {5, 6, 7},
 };
 \endcode
 
-In the case of vectors and rowvectors, the following shorthand notation can be used:
+For column or row vectors, implicit transposition is allowed.
+This means that a column vector can be initialized from a single row:
 \code
-VectorXd a {{1.5, 2.5, 3.5}};             // A vector with 3 rows
-RowVectorXd b {{1.0, 2.0, 3.0, 4.0}};     // A rowvector with 4 columns
+VectorXd a {{1.5, 2.5, 3.5}};             // A column-vector with 3 coefficients
+RowVectorXd b {{1.0, 2.0, 3.0, 4.0}};     // A row-vector with 4 coefficients
 \endcode
 
 \section TutorialMatrixCoeffAccessors Coefficient accessors

doc/snippets/Array_initializer_list_23_cxx11.cpp

@@ -0,0 +1,5 @@
+ArrayXXi a {
+  {1, 2, 3},
+  {3, 4, 5}
+};
+cout << a << endl;

doc/snippets/Array_initializer_list_cxx11.cpp

@@ -1,6 +0,0 @@
-Array<int, 2, 3> a {
-  {1, 2, 3},
-  {3, 4, 5}
-};
-Array<int, Dynamic, 1> v {{1, 2, 3, 4, 5}};
-cout << a << "\n\n" << v << endl;

doc/snippets/Array_initializer_list_vector_cxx11.cpp

@@ -0,0 +1,2 @@
+Array<int, Dynamic, 1> v {{1, 2, 3, 4, 5}};
+cout << v << endl;

doc/snippets/Matrix_initializer_list_23_cxx11.cpp

@@ -0,0 +1,5 @@
+MatrixXd m {
+  {1, 2, 3},
+  {4, 5, 6}
+};
+cout << m << endl;

doc/snippets/Matrix_initializer_list_cxx11.cpp

@@ -1,6 +0,0 @@
-Matrix<int, 2, 3> m {
-  {1, 2, 3},
-  {4, 5, 6}
-};
-VectorXi v {{1, 2}};
-cout << m << "\n\n" << v << endl;

doc/snippets/Matrix_initializer_list_vector_cxx11.cpp

@@ -0,0 +1,2 @@
+VectorXi v {{1, 2}};
+cout << v << endl;