adds a user model and specs

references #135 @01:20
creates a session controller and adds BDD gems

references #135 @00:40
adds a feature file for user login/register/logout

also adds the guard-cucumber gem and refactors the gemfile
references #135 @2h
adds HAML gem
adds specs for the session
harmonizes version strings
implements session tokens

references #135 @1:30
minimalistic change to the login story
implement login/logout

the login story is not passing yet because tracks cannot be listed yet
references #135 @3h
always validate passwords
implements track controller and an empty index

references #135 @00:30
references #136 @01:15
finalizes the user login/logout story and specs

closes #135 @00:20
create admin with rake admin::create

resolves #153 @00:20
makes scan more verbose, display tracks by title

resolves #136 @00:30
some work on the download and play features

play is not yet implemented
closes #132 @1:00
references #137 @00:30
make play and download actions restful
adds a player shim to the application layout
adds Jbuilder gem
removes play action, it's not needed anymore
player should be an id, not a class