0031171: Draw - support Unicode input / output in console on Windows

0031171: Draw - support Unicode input / output in console on Windows

System console is configured at DRAW start to use UTF-8 encoding, for cout and cin to deal correctly with Unicode symbols.
Use of std::wcout is avoided as it leads to corrupted output.

Command testgrid is improved to enforce UTF-8 encoding in child DRAW processes to preserve Unicode symbols in captured output.

Test bugs fclasses bug22125 is refactored:
- avoid dependency on external data file
- avoid producing snapshot
- check that Unicode name of the file created by OCCT procedure matches the name interpreted by Tcl functions