Merge #9

9: unused qualifications r=cuviper a=Pzixel

This code won't work on 0.1.43:
```rust
#![deny(trivial_numeric_casts)]
#![deny(unused_qualifications)]
extern crate num;
#[macro_use]
extern crate num_derive;
use num::ToPrimitive;

#[derive(ToPrimitive)]
pub enum SomeEnum {
    A = 1
}

fn main() {
    println!("{}", SomeEnum::A.to_i64().unwrap())
}
```
This is an attempt to fix it

Cargo.toml

@@ -8,7 +8,7 @@ categories = [ "science" ]
 license = "MIT/Apache-2.0"
 name = "num-derive"
 repository = "https://github.com/rust-num/num-derive"
-version = "0.1.43"
+version = "0.1.44"
 readme = "README.md"
 
 [dependencies]

RELEASES.md

@@ -1,3 +1,10 @@
+# Release 0.1.44
+
+- [The derived code now explicitly allows `unused_qualifications`][9], so users
+  that globally deny that lint don't encounter an error.
+
+[9]: https://github.com/rust-num/num-derive/pull/9
+
 # Release 0.1.43
 
 - [The derived code now explicitly allows `trivial_numeric_casts`][7], so users

src/lib.rs

@@ -72,6 +72,7 @@ pub fn from_primitive(input: TokenStream) -> TokenStream {
 
     let res = quote! {
         #[allow(non_upper_case_globals)]
+        #[allow(unused_qualifications)]
         const #dummy_const: () = {
             extern crate num as _num;
 
@@ -148,6 +149,7 @@ pub fn to_primitive(input: TokenStream) -> TokenStream {
 
     let res = quote! {
         #[allow(non_upper_case_globals)]
+        #[allow(unused_qualifications)]
         const #dummy_const: () = {
             extern crate num as _num;
 

tests/issue-9.rs

@@ -0,0 +1,18 @@
+#![deny(unused_qualifications)]
+extern crate num;
+#[macro_use]
+extern crate num_derive;
+use num::FromPrimitive;
+use num::ToPrimitive;
+
+#[derive(FromPrimitive, ToPrimitive)]
+pub enum SomeEnum {
+    A = 1
+}
+
+#[test]
+fn test_unused_qualifications() {
+    assert!(SomeEnum::from_u64(1).is_some());
+    assert!(SomeEnum::from_i64(-1).is_none());
+    assert!(SomeEnum::A.to_i64().is_some());
+}