TASK: Add codeblocks to code examples

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

docs/notifications.md

@@ -29,6 +29,7 @@ order is not guaranteed.
 To setup a registry instance to send notifications to endpoints, one must add
 them to the configuration. A simple example follows:
 
+```yaml
 notifications:
   endpoints:
     - name: alistener
@@ -38,6 +39,7 @@ them to the configuration. A simple example follows:
       timeout: 500ms
       threshold: 5
       backoff: 1s
+```
 
 The above would configure the registry with an endpoint to send events to
 `https://mylistener.example.com/event`, with the header "Authorization: Bearer
@@ -123,10 +125,12 @@ contains a subset of the data contained in Get and Put events. Specifically,
 only the digest and repository are sent.
 
 ```json
+{
   "target": {
     "digest": "sha256:d89e1bee20d9cb344674e213b581f14fbd8e70274ecf9d10c514bab78a307845",
     "repository": "library/test"
-},
+  }
+}
 ```
 
 > **Note**: As of version 2.1, the `length` field for event targets
@@ -140,7 +144,7 @@ The envelope contains one or more events, with the following json structure:
 
 ```json
 {
-	"events": [ ... ],
+  "events": [ "..." ]
 }
 ```
 
@@ -155,8 +159,8 @@ request coming to an endpoint.
 
 An example of a full event may look as follows:
 
-```json
-GET /callback
+```
+GET /callback HTTP/1.1
 Host: application/vnd.docker.distribution.events.v1+json
 Authorization: Bearer <your token, if needed>
 Content-Type: application/vnd.docker.distribution.events.v1+json
@@ -263,6 +267,7 @@ The following provides an example of a few endpoints that have experienced
 several failures and have since recovered:
 
 ```json
+{
   "notifications": {
     "endpoints": [
       {
@@ -283,7 +288,6 @@ several failures and have since recovered:
           "Failures": 0,
           "Errors": 46,
           "Statuses": {
-
           }
         }
       },
@@ -307,6 +311,7 @@ several failures and have since recovered:
       }
     ]
   }
+}
 ```
 
 If using notification as part of a larger application, it is _critical_ to