Add markdown CI (#5380)

docs/debian.md

@@ -1,15 +1,14 @@
-Debian Jessie
-===============
+# Debian Jessie
 
 Debian Jessie installation Notes:
 
-- Add 
+- Add
   
   ```GRUB_CMDLINE_LINUX="cgroup_enable=memory swapaccount=1"```
   
   to /etc/default/grub. Then update with
   
-  ```
+  ```ShellSession
    sudo update-grub
    sudo update-grub2
    sudo reboot
@@ -23,7 +22,7 @@ Debian Jessie installation Notes:
   
 - Add the Ansible repository and install Ansible to get a proper version
 
-  ```
+  ```ShellSession
   sudo add-apt-repository ppa:ansible/ansible
   sudo apt-get update
   sudo apt-get install ansible
@@ -34,5 +33,4 @@ Debian Jessie installation Notes:
 
   ```sudo apt-get install python-jinja2=2.8-1~bpo8+1 python-netaddr```
   
-  
 Now you can continue with [Preparing your deployment](getting-started.md#starting-custom-deployment)