Jebbs/DSFML — pull request #1 by nikibobi (2013-04-01 13:32:36+00:00)
Title: Added Color operators

Hi,
I have added the following operations to the `Color` struct:
* +, -, *, /
* +=, -=, *=, /=
* ==, !=

And also added `toString()` method.

I have tested them with the following unittest
```D
import dsfml.system;
import dsfml.window;
import dsfml.graphics;
import std.stdio;

void main()
{
writeln("Testing");
}

unittest
{
Color yellow = Color.Yellow;
Color blue = Color.Blue;

Color result = yellow + blue;
yellow += blue;
assert(result == Color.White);
assert(result == yellow);
assert(yellow != Color.Black);

yellow /= Color(255, 8, 16, 32);
writeln(yellow.toString());

assert((Color.Yellow + Color.Blue) == Color.White);
}
```