Clarify README's installation instructions

Add detail to the Rails installation sections and show default
configuration options. Also simplify example's usage and add link to find
more information on Rails middlewares.

README.md

@@ -1,3 +1,5 @@
+# Rack::LiveReload
+
 <a href="http://travis-ci.org/johnbintz/rack-livereload"><img src="https://secure.travis-ci.org/johnbintz/rack-livereload.png" /></a>
 [![Code Climate](https://codeclimate.com/github/johnbintz/rack-livereload.png)](https://codeclimate.com/github/johnbintz/rack-livereload)
 
@@ -7,35 +9,45 @@ Even supports browsers without WebSockets!
 
 Use this with [guard-livereload](http://github.com/guard/guard-livereload) for maximum fun!
 
-## Install
+## Installation
-
-`gem install rack-livereload`
-
-## Using in...
 
 ### Rails
 
+Add the gem to your Gemfile.
 
-In `config/environments/development.rb`:
+```ruby
+gem "rack-livereload", :group => :development
+```
+
+Then add the middleware to your Rails middleware stack by editing your `config/environments/development.rb`.
+
+```ruby
+# config/environments/development.rb
 
-``` ruby
 MyApp::Application.configure do
-  config.middleware.insert_after(ActionDispatch::Static, Rack::LiveReload)
+  # Add Rack::LiveReload to the bottom of the middleware stack with the default options.
-
+  config.middleware.use Rack::LiveReload
-  # ...or, change some options...
+  
-
+  # ...
-  config.middleware.insert_before(
-    Rack::Lock, Rack::LiveReload,
-    :min_delay => 500,
-    :max_delay => 10000,
-    :live_reload_port => 56789,
-    :host => 'myhost.cool.wow',
-    :ignore => [ %r{dont/modify\.html$} ]
-  )
 end
 ```
 
-### config.ru/Sinatra
+#### Tweaking the options
+
+```ruby
+# Specifying Rack::LiveReload options.
+config.middleware.use(Rack::LiveReload,
+  :min_delay        => 500,    # default 1000
+  :max_delay        => 10_000, # default 60_000
+  :live_reload_port => 56789,  # default 35729
+  :host             => 'myhost.cool.wow',
+  :ignore           => [ %r{dont/modify\.html$} ]
+)
+```
+
+In addition, Rack::LiveReload's position within middleware stack can be specified by inserting it relative to an exsiting middleware via `insert_before` or `insert_after`. See the [Rails on Rack: Adding a Middleware](http://guides.rubyonrails.org/rails_on_rack.html#adding-a-middleware) section for more detail.
+
+### Sinatra / config.ru
 
 ``` ruby
 require 'rack-livereload'