Add missing uses for FromPrimitive & ToPrimitive

src/sdl2/audio.rs

@@ -5,6 +5,7 @@ use std::mem;
 use std::c_str::CString;
 use std::c_vec::CVec;
 use std::borrow::ToOwned;
+use std::num::FromPrimitive;
 use libc;
 use libc::{c_int, size_t, c_void};
 use libc::{uint8_t};

src/sdl2/keycode.rs

@@ -1,4 +1,5 @@
 use std::hash::{self, Hash};
+use std::num::{FromPrimitive, ToPrimitive};
 
 #[deriving(PartialEq, Eq, FromPrimitive, Show, Copy)]
 pub enum KeyCode {

src/sdl2/scancode.rs

@@ -1,4 +1,5 @@
 use std::hash::{self, Hash};
+use std::num::{FromPrimitive, ToPrimitive};
 
 #[deriving(PartialEq, Eq, FromPrimitive, Show, Copy)]
 pub enum ScanCode {

src/sdl2/surface.rs

@@ -4,6 +4,7 @@ use get_error;
 use SdlResult;
 use std::ptr;
 use libc::{c_int, uint32_t};
+use std::num::FromPrimitive;
 use pixels;
 use render::BlendMode;
 use rwops;