doc: Typo in CustomizingEigen, introduced in previous commit.
Thanks to Christoph Hertzberg for noting this.

doc/I00_CustomizingEigen.dox

diff --git a/doc/I00_CustomizingEigen.dox b/doc/I00_CustomizingEigen.dox
index 43ac850..aa4514d 100644
--- a/doc/I00_CustomizingEigen.dox
+++ b/doc/I00_CustomizingEigen.dox
@@ -97,7 +97,7 @@
 
     // This constructor allows you to construct MyVectorType from Eigen expressions
     template<typename OtherDerived>
-    Vector3D(const Eigen::MatrixBase<OtherDerived>& other)
+    MyVectorType(const Eigen::MatrixBase<OtherDerived>& other)
         : Eigen::Vector3d(other)
     { }