docs: update readme

Author: daviddias

README.md

@@ -25,7 +25,6 @@ backed by an [IPFS Repo][repo] as its datastore for blocks, and uses [Bitswap][b
 ┌────────────────────┐
 │     BlockService   │
 └────────────────────┘
-           │
      ┌─────┴─────┐
      ▼           ▼
 ┌─────────┐ ┌───────┐
@@ -51,7 +50,7 @@ backed by an [IPFS Repo][repo] as its datastore for blocks, and uses [Bitswap][b
 ### npm
 
 ```sh
-> npm i ipfs-block-service
+> npm install ipfs-block-service
 ```
 
 ## Usage
@@ -75,19 +74,26 @@ const repo = new IPFSRepo('example')
 
 // create a block
 const data = new Buffer('hello world')
-multihashing(data, 'sha2-256', (err, hash) => {
-  if (err) throw err
+multihashing(data, 'sha2-256', (err, multihash) => {
+  if (err) {
+    throw err
+  }
 
-  const block = new Block(data, new CID(hash))
+  const cid = new CID(multihash)
+  const block = new Block(data, cid)
 
   // create a service
   const bs = new BlockService(repo)
 
   // add the block, then retrieve it
   bs.put(block, (err) => {
-    if (err) throw err
-    bs.get(block.cid, (err, b) => {
-      if (err) throw err
+    if (err) {
+      throw err
+    }
+    bs.get(cid, (err, b) => {
+      if (err) {
+        throw err
+      }
       console.log(block.data.toString() === b.data.toString())
       // => true
     })