Add support for prev/next/self links when returning paginated results. To do this: 1) change "data" envelope from an array to a dict 2) move the "data" array to the "collection" property, which is an array of elements in the collection. 3) add @links dict keyed by link relation: self, next, prev. Each relation is an array of dicts with uri and rel keys. In this case there is only one element, but there is nothing preventing a relation from having multiple url's. So this follows the formatting needed for the general case. Relations are present only if it makes sense. So first page has no prev and last page has no next. 4) add @total_size with number of element selected if they were not paginated. Replicates data in X-Count-Total header. Changed index to start at 1. So the first page is page_index 1 and not page_index 0. (So I am no longer surprised when I set page_index to 1 and am missing a bunch of records 8-)). Also a small fixup, json response ends with a newline so printing the data, or using curl makes sure that anything printing after the json output (like shell prompts) is on a new line. Tests added for all cases.

==========================
PostgreSQL/psycopg Backend
==========================

This are notes about PostqreSQL backend based on the psycopg adapter for
Roundup issue tracker.

Prerequisites
=============

To use PostgreSQL as backend for storing roundup data, you should
additionally install:

1. PostgreSQL 8.x or higher - http://www.postgresql.org/

2. The psycopg python interface to PostgreSQL:

     http://initd.org/software/initd/psycopg


Running the PostgreSQL unit tests
=================================

The user that you're running the tests as will need to be able to access
the postgresql database on the local machine and create and drop
databases. See the config values in 'test/db_test_base.py' 
about which database connection, name and user will be used.


Credit
======

The postgresql backend was originally submitted by Federico Di Gregorio
<fog@initd.org>