Update README and CHANGELOG for v0.3.0

CHANGELOG

@@ -1,4 +1,4 @@
-master
+v0.3.0 2018-08-21
 
 * 'pub' now supports Announce activities' default behavior. Upon receiving an
       Announce activity via S2S, it is added to the 'shares' property of

README.md

@@ -2,8 +2,6 @@
 
 `go get github.com/go-fed/activity`
 
-This repository supports `vgo` and is remotely verifiable.
-
 This repository contains three libraries for use in your golang applications:
 
 * `vocab`: An ActivityStreams Vocabulary library
@@ -11,6 +9,8 @@ This repository contains three libraries for use in your golang applications:
 * `pub`: ActivityPub SocialAPI (Client-to-Server) and FederateAPI
   (Server-to-Server)
 
+This repository supports `vgo` and is remotely verifiable.
+
 This library is biased. It forgoes understanding JSON-LD in exchange for static
 typing. It provides a large amount of default behavior to let Social,
 Federated, or both kinds of ActivityPub applications just work.
@@ -20,7 +20,7 @@ documentation for every version of this library.
 
 ## Status
 
-**0.2.1** ([Semantic Versioning](https://semver.org/))
+**0.3.0** ([Semantic Versioning](https://semver.org/))
 
 An [official implementation report](https://activitypub.rocks/implementation-report/)
 was last submitted for version **0.2.0** [here](https://github.com/w3c/activitypub/issues/318).