*, +, ? don't backtrack

[kivikakk]

Here's some simple test cases demonstrating this:

    try testMatch("a*a", .ascii, "aa");
    try testMatch("a+a", .ascii, "aa");
    try testMatch("a?a", .ascii, "a");

These should all pass, but currently all fail. I'm currently staring down the main file to see how I might implement it, but I might not come through with the goods.