This change allows now having these variables as array sizes that
are not Variable Length Arrays like in structs for example.
To note however that this changes the type from unsigned int to an
implementation defined type which usually `int` which is signed and
not unsigned.
This helps make it easier to distinguish SFML files from CSFML files.
This is especially important for CSFML private headers which are
often C++ code with .hpp file extensions. This change means SFML and
CSFML can use headers with the same name without conflict.
ZXShady