Add allocation so searchables and search results

This requires the Allocation class to have a __str__ method and a field
called `search_fields`.
Install service app to external locations
Initial service models
Initial service form
Initial Service views
Service detail page
Service edit/form page
Service list page
add service urls
Initial south migrations and random __init__.py file
Initial service css
Show the services a system is a member of on the system's detail page
A script to import an initial set of services from a spreadsheet
Add the compiler backend functions for searching services and add a new 'service' directive.
Display service objects in search results
Show service attibutes on the search "Help" widget.
Add a JSON API for exporting a list of service objects
Add a JSON api for importing a JSON blob representing a set of services

This api is designed to injest a JSON blob similar to the one exported
via the service export API.
Import/export API tests