[BUG] Virtual argument's virtual path is case-sensitive

[Coryf88]

Describe the bug
--virtual's virtual path is case-sensitive

To Reproduce

1. Create file test.cpp, containing #include "\A3\3den\ui\macros.inc"
2. Execute sqfvm.exe --parse-only --virtual "P:\a3|a3" --input-config test.cpp
3. See error Failed to include '\A3\3den\ui\macros.inc'
4. Execute sqfvm.exe --parse-only --virtual "P:\a3|A3" --input-config test.cpp
5. Notice no error.

Expected behavior
Virtual path to be case-insensitive.

Screenshots
N/A

Additional context
N/A

[X39]

Limitation due to compatibility needs with unix.

While arma is indeed, case-insensitive, doing it with SQF-VM would require additional muscle work and double the memory footprint for certain things (eg. config tree, assembly size)

needs to be decided wether to implement this (and potentially fail on unix systems with the same code) or not