Reword docs

Co-Authored-By: Hong Minhee <hong.minhee@gmail.com>

CHANGES.md

@@ -37,10 +37,11 @@ To be released.
         an extension method of the same name.
      -  Added `IStore.IterateStateReferences()` method.
  -  `Swarm` constructor became to receive `BlockChain<T>`.  [[#324]]
- -  `Swarm` became to have type parameter `T` that reprsents action type as
+ -  `Swarm` became to have type parameter `T` to represent an action type as
     like as `BlockChain<T>`.  [[#324]]
- -  Methods that take `BlockChain<T>` as a parameter in `Swarm` no longer take
-    `BlockChain<T>`. And they are no longer the generic methods.  [[#324]]
+ -  Methods  in `Swarm` that had taken a parameter of `BlockChain<T>` type
+    became to neither longer take `BlockChain<T>` nor a generic method.
+    Because the `Swarm` constructor takes it instead.  [[#324]]
 
 ### Added interfaces