codingstyle: Fix indent for templates.html.tmpl

We just merged a fix to templates.html.tmpl where we had an extra </div>
tag.  These errors are made more common by code that isn't properly
indented.  Fix this file to make it easier to see the nesting of the
document.  All tabs have been replaced with 4 spaces as per community
style guidelines.

Signed-off-by: Adam Litke <agl@linux.vnet.ibm.com>