add data_mapper to gemfile
add blog index page to site and add links from homepage to blog
add new post form
display all posts on blog
add permalink and fix order of get blog calls
add post not found error handling, extra links for next lessons in index
add lesson 4 index
add cookies to lesson 4 to track visits
not really sure
add sinatra-contrib to gemfile
add Gemfile.lock to gitignore
Revert "add cookies to lesson 4 to track visits"

This reverts commit cb62fe0610051968f316fd94fbe2ad321bfdd605.

Conflicts:

	views/lesson4/index.erb
	web.rb
fix bug with datamapper default database
add sign up page to blog
add welcome page for blog sign up
add user model
add cookie with hash value and appropriate redirects
add user login page
change cookie path to /
changed cookie string value