[PATCH v2] include: Add corecrt_wstring.h header.

[Jacek Caban]

Signed-off-by: Jacek Caban <jacek(a)codeweavers.com>
---
  include/msvcrt/corecrt_wstring.h | 88 ++++++++++++++++++++++++++++++++
  include/msvcrt/string.h          | 74 +--------------------------
  include/msvcrt/wchar.h           | 59 +--------------------
  3 files changed, 90 insertions(+), 131 deletions(-)
  create mode 100644 include/msvcrt/corecrt_wstring.h