Clean up trailing whitespace

CONTRIBUTING.md

@@ -22,7 +22,7 @@ efforts from contributors on the same issue.
   master you may be asked to rebase your changes.
 
 - Commits should be as small as possible, while ensuring that each commit is
-  correct independently (i.e., each commit should compile and pass tests). 
+  correct independently (i.e., each commit should compile and pass tests).
 
 - If your patch is not getting reviewed or you need a specific person to review
   it, you can @-reply a reviewer asking for a review in the pull request or a

serde/src/ser/impls.rs

@@ -513,7 +513,7 @@ impl Serialize for net::IpAddr {
             }
         } else {
             match *self {
-                net::IpAddr::V4(ref a) => 
+                net::IpAddr::V4(ref a) =>
                     serializer.serialize_newtype_variant("IpAddr", 0, "V4", a),
                 net::IpAddr::V6(ref a) =>
                     serializer.serialize_newtype_variant("IpAddr", 1, "V6", a),