Merge pull request #318 from zeke/master

A new auth:whoami command and some developer documentation
ideal plugins commands
ideal ps commands
cleanup/ideal for accounts
ideal sharing commands

more sharing fixes
ideal version command
bump heroku-api dependency to 0.1.7
cleanup for pg commands
cleanup pgbackups
display current and new versions during update
override heroku.rb user-agent in request headers
get rid of extract_option
fix placement of example in version
ideal update commands
ideal account
ideal auth
ideal help
add missing validate_arguments! to account, auth, update and version
Make 'status' dynamic with HEROKU_HOST
Address the actual issue. :)