Auto merge of #16 - pyfisch:ipaddr, r=Manishearth

Add Ipv4Addr and Ipv6Addr for use in rust-url

Needed for servo/rust-url#135.

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src/lib.rs

@@ -17,6 +17,7 @@ use std::collections::hash_state;
 use std::hash::Hash;
 use std::marker::PhantomData;
 use std::mem::{size_of, transmute};
+use std::net::{Ipv4Addr, Ipv6Addr};
 use std::sync::Arc;
 use std::rc::Rc;
 
@@ -258,4 +259,5 @@ macro_rules! known_heap_size(
 known_heap_size!(0, u8, u16, u32, u64, usize);
 known_heap_size!(0, i8, i16, i32, i64, isize);
 known_heap_size!(0, bool, f32, f64);
+known_heap_size!(0, Ipv4Addr, Ipv6Addr);
 known_heap_size!(0, PhantomData<T>);