Update example database.yml

Changes to the environment used on CI and database configured using
Postgres.app.
Seed just needed configuration by default

Also removes unused configurations from seed files.
Bundle install in bootstrap script
Write instructions about bootstrap Neighborly
Remove extra parenthesis in README

[ci skip]
Remove database specialization in travis.yml
Define 3000 as default port of rack server
Merge pull request #289 from neighborly/im-project-init

Bootstrap script