[USETUP][NTDLL_APITEST][KBDROST] Allow non-Latin codepage users to build ReactOS...

[USETUP][NTDLL_APITEST][KBDROST] Allow non-Latin codepage users to build ReactOS on MSVC (Retrial of #1150) (#1168)

- The converter is code7bit I made. code7bit: https://github.com/katahiromz/code7bit
- This converter converts non-clean characters in string literals.
- However I couldn't erase a ton of codepage C4819 warnings.
- CORE-15447

You can edit an European source file as follows:
- Right click the file in the Solution Explorer.
- Select "Open With...".
- Choose "C++ Source Code Editor (with encoding)".
- Choose "Central European (Windows) - Codepage 1260".