Auto merge of #11 - Manishearth:with-key, r=Ms2ger

Add FnvHasher::with_key()

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Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "fnv"
-version = "1.0.3"
+version = "1.0.4"
 authors = ["Alex Crichton <alex@alexcrichton.com>"]
 description = "Fowler–Noll–Vo hash function"
 license = "Apache-2.0 / MIT"

lib.rs

@@ -78,8 +78,16 @@ impl Default for FnvHasher {
     }
 }
 
-impl Hasher for FnvHasher {
+impl FnvHasher {
+    /// Create an FNV hasher starting with a state corresponding
+    /// to the hash `key`.
+    #[inline]
+    pub fn with_key(key: u64) -> FnvHasher {
+        FnvHasher(key)
+    }
+}
 
+impl Hasher for FnvHasher {
     #[inline]
     fn finish(&self) -> u64 {
         self.0