use Eigen::aligned_allocator for std::vector/map containing Eigen object

Use of Eigen::aligned_allocator within stl containers.

After error : 

my_program: path/to/eigen/Eigen/src/Core/DenseStorage.h:44:
Eigen::internal::matrix_array<T, Size, MatrixOptions, Align>::internal::matrix_array()
[with T = double, int Size = 2, int MatrixOptions = 2, bool Align = true]:
Assertion `(reinterpret_cast<size_t>(array) & 0xf) == 0 && "this assertion
is explained here: http://eigen.tuxfamily.org/dox/UnalignedArrayAssert.html
     READ THIS WEB PAGE !!! ****"' failed.