Apply @Jesus' plugin docs reformatting from #1849

docs/plugins.md

@@ -1,28 +1,38 @@
 ## Plugins
 
-Puma 3.0 added support for plugins that can augment configuration and service operations.
+Puma 3.0 added support for plugins that can augment configuration and service
+operations.
 
 2 canonical plugins to look to aid in development of further plugins:
 
-* [tmp\_restart](https://github.com/puma/puma/blob/master/lib/puma/plugin/tmp_restart.rb): Restarts the server if the file `tmp/restart.txt` is touched
-* [heroku](https://github.com/puma/puma-heroku/blob/master/lib/puma/plugin/heroku.rb): Packages up the default configuration used by puma on Heroku
+* [tmp\_restart](https://github.com/puma/puma/blob/master/lib/puma/plugin/tmp_restart.rb):
+  Restarts the server if the file `tmp/restart.txt` is touched
+* [heroku](https://github.com/puma/puma-heroku/blob/master/lib/puma/plugin/heroku.rb):
+  Packages up the default configuration used by puma on Heroku
 
-Plugins are activated in a puma configuration file (such as `config/puma.rb'`) by adding `plugin "name"`, such as `plugin "heroku"`.
+Plugins are activated in a puma configuration file (such as `config/puma.rb'`)
+by adding `plugin "name"`, such as `plugin "heroku"`.
 
-Plugins are activated based simply on path requirements so, activating the `heroku` plugin will simply be doing `require "puma/plugin/heroku"`. This allows gems to provide multiple plugins (as well as unrelated gems to provide puma plugins).
+Plugins are activated based simply on path requirements so, activating the
+`heroku` plugin will simply be doing `require "puma/plugin/heroku"`. This
+allows gems to provide multiple plugins (as well as unrelated gems to provide
+puma plugins).
 
 The `tmp_restart` plugin is bundled with puma, so it can always be used.
 
 To use the `heroku` plugin, add `puma-heroku` to your Gemfile or install it.
 
 ### API
 
-At present, there are 2 hooks that plugins can use: `start` and `config`.
+## Server-wide hooks
 
-`start` runs when the server has started and allows the plugin to start other functionality to augment puma.
+Plugins can use a couple of hooks at server level: `start` and `config`.
 
-`config` runs when the server is being configured and is passed a `Puma::DSL` object that can be used to add additional configuration.
+`start` runs when the server has started and allows the plugin to start other
+functionality to augment puma.
 
-Any public methods in `Puma::Plugin` are the public API that any plugin may use.
+`config` runs when the server is being configured and is passed a `Puma::DSL`
+object that can be used to add additional configuration.
 
-In the future, more hooks and APIs will be added.
+Any public methods in `Puma::Plugin` are the public API that any plugin may
+use.