Add sorting/styling to the Singularity image list table.

Resolves #25 (closed).

content/applications/user_software/using_singularity.md

@@ -31,14 +31,17 @@ Publically available Docker images can be found at [Docker Hub](http://hub.docke
 convenience, HCC also provides a set of images on [Docker Hub](https://hub.docker.com/u/unlhcc/)
 known to work on HCC resources.  
 
-
 ### Available Images at HCC
 
 The following table lists the currently available images and the command
 to run the software.
 
+{{< sorttable >}}
+
 {{< readfile file="static/markdown/singularity-images.md" markdown="true" >}}
 
+{{< /sorttable >}}
+
 {{% notice note %}}
 If you would like to request an image to be added, please fill out the
 HCC [Software Request Form](http://hcc.unl.edu/software-installation-request)