Add dual dev/publish modes to quickstart script

Certain configuration options are more useful in production than they
are in development. Some examples might be absolute URLs, external
analytics service identifiers, Disqus comments, etc. This version of the
quickstart script creates two configuration files: one for development
and the other for use when publishing. In addition, the related docs
have been expanded considerably. Last but not least, the quickstart
script will now detect whether there is a project folder associated with
the currently active virtualenv (if any) and use it by default.

pelican/tools/templates/pelican.conf.py.in

@@ -1,25 +0,0 @@
-#!/usr/bin/env python
-# -*- coding: utf-8 -*- #
-
-AUTHOR = u"$author"
-SITENAME = u"$sitename"
-SITEURL = ''
-
-TIMEZONE = 'Europe/Paris'
-
-DEFAULT_LANG='$lang'
-
-# Blogroll
-LINKS =  (
-    ('Pelican', 'http://docs.notmyidea.org/alexis/pelican/'),
-    ('Python.org', 'http://python.org'),
-    ('Jinja2', 'http://jinja.pocoo.org'),
-    ('You can modify those links in your config file', '#')
-         )
-
-# Social widget
-SOCIAL = (
-          ('You can add links in your config file', '#'),
-         )
-
-DEFAULT_PAGINATION = $default_pagination