STYLE: Replace vtksys_stl and vtksys_ios:: with std::
In the early days of VTK, support for stl was not portable. vtksys_stl and vtksys_ios provided a portable implementation of the stl. Now, all of the VTK supported compilers have portable stl implementations.
This patch:
- Replaces the vtksys_ios:: with std::.
- Replaces the vtksys_stl:: with std::.
- Removes "using" statements for stl