Merge pull request #65 from ctshryock/dev_db

shared-database:5mb -> heroku-postgresql:dev
extract these shell helpers into their own module
extract bootstrap_bundler
use LockfileParser in detect
extract gem_version logic into it's own method
use LockfileParser for rails 2
have rack use gem_version
warn people when they don't have a lockfile
rails 4 buildpack
setup assets precompile for rails 4
redo default process types
don't write database.yml for rails 4
add Rails 4 to detect array
include the beta into the rails 4 beta
rails still needs DATABASE_URL to run the assets:precompile rake task
fail deploy on assets fail on rails 4
update to Bundler 1.3.0
bump to v51
update changelog
add date to v50 changelog