Prettier long string breaking.

Author: TeXitoi

src/test/bench/shootout-mandelbrot.rs

@@ -21,8 +21,8 @@ static LIMIT: f64 = 2.0;
 fn main() {
     let args = std::os::args();
     let (w, mut out) = if args.len() < 2 {
-        println("Test mode: do not dump the image because it's not utf8,"
-                + " which interferes with the test runner.");
+        println("Test mode: do not dump the image because it's not utf8, \
+                which interferes with the test runner.");
         (1000, ~DummyWriter as ~Writer)
     } else {
         (from_str(args[1]).unwrap(),