added data mapper
datamapper setup and link.rb
browsing links
adding links
adding tags to the links
searching tags
Adding user accounts
password confirmation needed
handling input errors in psw field
check if email is unique
prevents duplicate registrations
Added Rake tasks
Sign in
sign out + refactoring
added header to the homepage
added buttons in the header
added 'add new link' button
styled the frontpage
started styling add links page
merged