Update .gitignore.
Add life expectancy data file.
Update life expectancy data with correct data types.
Create initial Sinatra app.

This app handles the /patient/:id route by looking up the patient in the
SHIN-NY, comparing the patient's name with the querystring parameter,
and returning life expectancy and vitals data.
Add config.ru for Heroku.
Add Gemfile.lock for Heroku.