fixed problems with colon character

This pull should fixes problems with the colon character when used on pseudo-classes and other new CSS3 cases.

Before this code:

    a:hover {
        color:black;
    }
    ::selection {
        color:black;
    }

was converted in:

    a: hover {
        color: black;
    }
    : : selection {
        color: black;
    }

Notice the extra white-spaces added after each colon character.
My fix should have fixed this problem.