core: consider a specific strategy for windows

This solution should be unified when MSVC compiler will behave properly

include/eigenpy/eigen-from-python.hpp

@@ -290,10 +290,16 @@ struct eigen_from_py_impl<MatType, Eigen::MatrixBase<MatType> > {
   static void registration();
 };
 
+#ifdef EIGENPY_MSVC_COMPILER
 template <typename EigenType>
 struct EigenFromPy<EigenType,
                    typename boost::remove_reference<EigenType>::type::Scalar>
-    : eigen_from_py_impl<EigenType> {};
+#else
+template <typename EigenType, typename _Scalar>
+struct EigenFromPy
+#endif
+    : eigen_from_py_impl<EigenType> {
+};
 
 template <typename MatType>
 void *eigen_from_py_impl<MatType, Eigen::MatrixBase<MatType> >::convertible(

include/eigenpy/eigen-to-python.hpp

@@ -155,9 +155,14 @@ struct eigen_to_py_impl_tensor {
 
 EIGENPY_DOCUMENTATION_END_IGNORE
 
+#ifdef EIGENPY_MSVC_COMPILER
 template <typename EigenType>
 struct EigenToPy<EigenType,
                  typename boost::remove_reference<EigenType>::type::Scalar>
+#else
+template <typename EigenType, typename _Scalar>
+struct EigenToPy
+#endif
     : eigen_to_py_impl<EigenType> {
   static PyTypeObject const* get_pytype() { return getPyArrayType(); }
 };