Add table of contents to sidebar when there is a table of contents

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docs/dns.md

@@ -2,27 +2,30 @@
 
 > Note: This is a work in progress.
 
-### DNS Versions
+## DNS Versions
 
 There are many different DNS servers 'in the wild'.  Some of the popular ones on Linux are BIND, dnsmasq, and pdns.  Windows has its own built-in DNS server as well as Unbound, Posadis, and more.  A full list of DNS packages can be found on Wikipedia under [Comparison of DNS Server Software](http://en.wikipedia.org/wiki/Comparison_of_DNS_server_software).  In addition to the various DNS packages, there are tens of thousands of [Managed DNS Providers](http://en.wikipedia.org/wiki/List_of_managed_DNS_providers) out that all have different DNS interfaces.
 
-### Focus
+## Focus
 
 Because there are so many different DNS server packages out there as well as a tremendous number of Managed DNS Providers, we will focus on the concepts of DNS as well as providing examples in the 'BIND' format so you can adapt the information to your own server package or managed DNS provider.
 
-### Assumptions
+## Assumptions
 
 * We assume you have a passing familiarity with DNS.  If not, you can read an [in-depth article](http://www.diaryofaninja.com/blog/2012/03/03/devops-dns-for-developers-ndash-now-therersquos-no-excuse-not-to-know) on DNS.  But basically you need to know that DNS changes names (like example.tld) into addresses (like 127.0.0.1)
 * We assume you already have a domain name registered and pointed to your favorite Managed DNS Provider or have your own BIND DNS server running.
 * You have a server on the internet and are about to follow the instructions in the [README](https://github.com/dokku/dokku/blob/master/README.md) to get dokku installed.  Don't do the install just yet though.
 
+## Caching
 
-### HELP!
+Please remember that DNS relies heavily on _caching_.  Changes you make to DNS could take anywhere from a few seconds to a few *days* to propagate.  If you tried surfing to example.tld, then changed the IP address in DNS, it could be a while before your computer picks up on the changes.
+
+## HELP!
 
 Don't be afraid to ask if you need help.  Create a [new issue](https://github.com/dokku/dokku/issues) and someone will be glad to assist you.
 
 
-# Getting started
+## Getting started
 
 For the examples, we will use the domain name `example.tld` and the IP address `127.0.0.1`.
 
@@ -30,17 +33,11 @@ Dokku uses DNS to differentiate between apps on your dokku-powered server.  If y
 
 To get started, you need to know the IP address of your dokku server.  Connect to it and run `ifconfig` or `ip addr` to see the IP address.
 
-# Caching
-
-Please remember that DNS relies heavily on _caching_.  Changes you make to DNS could take anywhere from a few seconds to a few *days* to propagate.  If you tried surfing to example.tld, then changed the IP address in DNS, it could be a while before your computer picks up on the changes.
-
-## The two methods
-
 Now you have to make a decision about your domain.  Do you want everything and anything at `example.tld` to go to your dokku server, or would you rather use a 'sub domain' for your dokku server?
 
 In other words, do you want your applications on your dokku server accessible via `myapp.example.tld` or via `myapp.myserver.example.tld`?
 
-### Using a sub-domain (myapp.myserver.example.tld)
+#### Using a sub-domain (myapp.myserver.example.tld)
 
 Using a sub-domain is easy.  When you set up your server, you probably gave it a name like `myserver.example.tld`.
 
@@ -75,7 +72,7 @@ If they all return your IP address, you have set DNS up properly for dokku.  You
 
 Proceed with the setup instructions in the [README](https://github.com/dokku/dokku/blob/master/README.md)
 
-### Using the root of your domain (myapp.example.tld)
+#### Using the root of your domain (myapp.example.tld)
 
 This section is a work in progress.  It is incomplete.