Properly note when 0.5.0 features were released

[ci skip]

docs/checks-examples.md

@@ -1,5 +1,7 @@
 # Zero Downtime Deploys
 
+> Plugin management is New as of 0.5.0
+
 ```
 checks <app>                                                                                 Show zero-downtime status
 checks:disable <app>                                                                         Disable zero-downtime checks

docs/deployment/dockerfiles.md

@@ -42,13 +42,15 @@ Setting `$DOKKU_DOCKERFILE_CACHE_BUILD` to `true` or `false` will enable or disa
 
 ### Procfiles and Multiple Processes
 
+> New as of 0.5.0
+
 You can also customize the run command using a `Procfile`, much like you would on Heroku or
 with a buildpack deployed app. The `Procfile` should contain one or more lines defining [process
 types and associated commands](https://devcenter.heroku.com/articles/procfile#declaring-process-types).
 When you deploy your app a Docker image will be built, the `Procfile` will be extracted from the image
 (it must be in the folder defined in your `Dockerfile` as `WORKDIR` or `/app`) and the commands
 in it will be passed to `docker run` to start your process(es). Here's an example `Procfile`:
- 
+
 ```
 web: bin/run-prod.sh
 worker: bin/run-worker.sh

docs/dokku-storage.md

@@ -1,8 +1,8 @@
 # Dokku Core Storage Plugin
 
-> Spanking New as of 0.5.0
+> New as of 0.5.0
 
-As of Dokku 0.5.0, the preferred method to mount external containers to a dokku managed container, is to use the dokku storage plugin.
+The preferred method to mount external containers to a dokku managed container, is to use the dokku storage plugin.
 
 
 ```shell

docs/nginx.md

@@ -10,6 +10,8 @@ nginx:error-logs <app> [-t]
 
 ## Customizing the nginx configuration
 
+> New as of 0.5.0
+
 Dokku uses a templating library by the name of [sigil](https://github.com/gliderlabs/sigil) to generate nginx configuration for each app. If you'd like to provide a custom template for your application, there are a couple options:
 
 - Copy the following example template to a file named `nginx.conf.sigil` and either:

docs/proxy.md

@@ -1,5 +1,7 @@
 # Proxy plugin
 
+> New as of 0.5.0
+
 As of dokku 0.5.0, the proxy functionality has been decoupled from the nginx-vhosts plugin into the proxy plugin. In the future this will allow other proxy software (HAproxy for example) to be used instead of nginx.
 
 ```