Remove Signed trait and add SignedInt trait

The methods have been moved into Float and SignedInt

lib.rs

@@ -60,7 +60,7 @@ use std::io::fs::PathExtensions;
 use std::io::stdio::StdWriter;
 use std::io::{File, ChanReader, ChanWriter};
 use std::io;
-use std::num::{Int, FloatMath};
+use std::num::{Float, FloatMath, Int};
 use std::os;
 use std::string::String;
 use std::task::TaskBuilder;

stats.rs

@@ -461,6 +461,7 @@ mod tests {
 
     macro_rules! assert_approx_eq(
         ($a:expr, $b:expr) => ({
+            use std::num::Float;
             let (a, b) = (&$a, &$b);
             assert!((*a - *b).abs() < 1.0e-6,
                     "{} is not approximately equal to {}", *a, *b);