Add Gemfile for handling dependencies using bundler.

- Add Gemfile with Sinatra gem.
- Include Gemfile.lock.
Add rack config file and Web class.

- Add config.ru for use with Rack.
- Add web.rb (Web class) to handle entry point for Sinatra.
Set acceptable versions in Gemfile.
Add Slim template system with index view.

- Add slim dependency to Gemfile.
- Add index view for root requests.
- Update web class to use Slim templates and load views.
Include partials functionality in project.

- Add sinatra-partial gem dependency.
- Set partial template engine and register Partial extension.
Move common HTML from index into layout view.
Add stylesheet to layout view.

- Set class on body element.
Setup database connection to Postgres.

- Add pg gem for dependency management and requiring.
- Add before filter to test if database can be connected and then establishing connection.
Handle connection test without using exceptions.

- Use halt method in filter when ping to db fails.