move also inverse() to ReturnByValue, by doing a solve on NestByValue<Identity>.

also: adding resize() to MatrixBase was really needed ;)

Eigen/src/Core/MatrixBase.h

@@ -189,7 +189,7 @@ template<typename Derived> class MatrixBase
     /** \returns the size of the inner dimension according to the storage order,
       * i.e., the number of rows for a columns major matrix, and the number of cols otherwise */
     int innerSize() const { return (int(Flags)&RowMajorBit) ? this->cols() : this->rows(); }
-    
+
     /** Only plain matrices, not expressions may be resized; therefore the only useful resize method is
       * Matrix::resize(). The present method only asserts that the new size equals the old size, and does
       * nothing else.
@@ -202,7 +202,7 @@ template<typename Derived> class MatrixBase
       */
     void resize(int rows, int cols)
     { ei_assert(rows == this->rows() && cols == this->cols() && "MatrixBase::resize() does not actually allow to resize."); }
-    
+
 #ifndef EIGEN_PARSED_BY_DOXYGEN
     /** \internal the plain matrix type corresponding to this expression. Note that is not necessarily
       * exactly the return type of eval(): in the case of plain matrices, the return type of eval() is a const