Refine database.yml template

There should be two configuration options for database.yml. Either
configuring with attributes or configuring with data bags this makes
those two choices a bit more clear and prevents a bug that causes the
chef run to fail when the database databag attribute isn't defined.
Set the COMMUNITY_SITE_DATABASE_URL from a data bag value
binary for node is nodejs, not node
nginx serves sitemaps
Merge pull request #8 from opscode-cookbooks/bcobb/opscode-community-site-url

Set the COMMUNITY_SITE_DATABASE_URL from a data bag value
Merge pull request #7 from opscode-cookbooks/no-database-attribute

Refine database.yml template
Merge pull request #10 from opscode-cookbooks/bcobb/nginx-serves-sitemaps

nginx serves sitemaps
add rake db:seed to deploy resource

This adds the rake db:seed command to the deploy resource to ensure
the database gets populated with the ICLA/CCLA. This is done during
the deployment after restart, as the database will be set up, and we
want to ensure that this happens. The rake task itself is idempotent,
so re-running it should have no side effects on the database.

This also ensures the proper version of postgresql is used based on
the platform. Due to path locations, the `db:migrate` and `db:seed`
commands were failing at different points. This adds an attribute for
the postgres version. By default it will be 9.1, and can be changed by
the end user if necessary.